P. 109 of Theorem List - Intuitionistic Logic Explorer

Theorem List for Intuitionistic Logic Explorer - 10801-10900   *Has distinct variable group(s)

Type	Label	Description
Statement
Theorem	frecuzrdgrclt 10801*	The function R (used in the definition of the recursive definition generator on upper integers) yields ordered pairs of integers and elements of S. Similar to frecuzrdgrcl 10796 except that S and T need not be the same. (Contributed by Jim Kingdon, 22-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   =>    |- ( ph -> R : om --> ( ( ZZ>= ` C ) X. S ) )
Theorem	frecuzrdgg 10802*	Lemma for other theorems involving the the recursive definition generator on upper integers. Evaluating R at a natural number gives an ordered pair whose first element is the mapping of that natural number via G. (Contributed by Jim Kingdon, 23-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   &    |- ( ph -> N e. om )   &    |- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , C )   =>    |- ( ph -> ( 1st ` ( R ` N ) ) = ( G ` N ) )
Theorem	frecuzrdgdomlem 10803*	The domain of the result of the recursive definition generator on upper integers. (Contributed by Jim Kingdon, 24-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   &    |- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , C )   =>    |- ( ph -> dom ran R = ( ZZ>= ` C ) )
Theorem	frecuzrdgdom 10804*	The domain of the result of the recursive definition generator on upper integers. (Contributed by Jim Kingdon, 24-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   =>    |- ( ph -> dom ran R = ( ZZ>= ` C ) )
Theorem	frecuzrdgfunlem 10805*	The recursive definition generator on upper integers produces a a function. (Contributed by Jim Kingdon, 24-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   &    |- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , C )   =>    |- ( ph -> Fun ran R )
Theorem	frecuzrdgfun 10806*	The recursive definition generator on upper integers produces a a function. (Contributed by Jim Kingdon, 24-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   =>    |- ( ph -> Fun ran R )
Theorem	frecuzrdgtclt 10807*	The recursive definition generator on upper integers is a function. (Contributed by Jim Kingdon, 22-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   &    |- ( ph -> P = ran R )   =>    |- ( ph -> P : ( ZZ>= ` C ) --> S )
Theorem	frecuzrdg0t 10808*	Initial value of a recursive definition generator on upper integers. (Contributed by Jim Kingdon, 28-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   &    |- ( ph -> P = ran R )   =>    |- ( ph -> ( P ` C ) = A )
Theorem	frecuzrdgsuctlem 10809*	Successor value of a recursive definition generator on upper integers. See comment in frec2uz0d 10785 for the description of G as the mapping from om to ( ZZ>= ` C ). (Contributed by Jim Kingdon, 29-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   &    |- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , C )   &    |- ( ph -> P = ran R )   =>    |- ( ( ph /\ B e. ( ZZ>= ` C ) ) -> ( P ` ( B + 1 ) ) = ( B F ( P ` B ) ) )
Theorem	frecuzrdgsuct 10810*	Successor value of a recursive definition generator on upper integers. (Contributed by Jim Kingdon, 29-Apr-2022.)
|- ( ph -> C e. ZZ )   &    |- ( ph -> A e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. ( ZZ>= ` C ) /\ y e. S ) ) -> ( x F y ) e. S )   &    |- R = frec ( ( x e. ( ZZ>= ` C ) , y e. T |-> <. ( x + 1 ) , ( x F y ) >. ) , <. C , A >. )   &    |- ( ph -> P = ran R )   =>    |- ( ( ph /\ B e. ( ZZ>= ` C ) ) -> ( P ` ( B + 1 ) ) = ( B F ( P ` B ) ) )
Theorem	uzenom 10811	An upper integer set is denumerable. (Contributed by Mario Carneiro, 15-Oct-2015.)
|- Z = ( ZZ>= ` M )   =>    |- ( M e. ZZ -> Z ~~ om )
Theorem	frecfzennn 10812	The cardinality of a finite set of sequential integers. (See frec2uz0d 10785 for a description of the hypothesis.) (Contributed by Jim Kingdon, 18-May-2020.)
|- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 )   =>    |- ( N e. NN0 -> ( 1 ... N ) ~~ ( `' G ` N ) )
Theorem	frecfzen2 10813	The cardinality of a finite set of sequential integers with arbitrary endpoints. (Contributed by Jim Kingdon, 18-May-2020.)
|- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 )   =>    |- ( N e. ( ZZ>= ` M ) -> ( M ... N ) ~~ ( `' G ` ( ( N + 1 ) - M ) ) )
Theorem	frechashgf1o 10814	G maps om one-to-one onto NN0. (Contributed by Jim Kingdon, 19-May-2020.)
|- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 )   =>    |- G : om -1-1-onto-> NN0
Theorem	frec2uzled 10815*	The mapping G (see frec2uz0d 10785) preserves order. (Contributed by Jim Kingdon, 24-Feb-2022.)
|- ( ph -> C e. ZZ )   &    |- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , C )   &    |- ( ph -> A e. om )   &    |- ( ph -> B e. om )   =>    |- ( ph -> ( A C_ B <-> ( G ` A ) <_ ( G ` B ) ) )
Theorem	fzfig 10816	A finite interval of integers is finite. (Contributed by Jim Kingdon, 19-May-2020.)
|- ( ( M e. ZZ /\ N e. ZZ ) -> ( M ... N ) e. Fin )
Theorem	fzfigd 10817	Deduction form of fzfig 10816. (Contributed by Jim Kingdon, 21-May-2020.)
|- ( ph -> M e. ZZ )   &    |- ( ph -> N e. ZZ )   =>    |- ( ph -> ( M ... N ) e. Fin )
Theorem	fzofig 10818	Half-open integer sets are finite. (Contributed by Jim Kingdon, 21-May-2020.)
|- ( ( M e. ZZ /\ N e. ZZ ) -> ( M..^ N ) e. Fin )
Theorem	nn0ennn 10819	The nonnegative integers are equinumerous to the positive integers. (Contributed by NM, 19-Jul-2004.)
|- NN0 ~~ NN
Theorem	nnenom 10820	The set of positive integers (as a subset of complex numbers) is equinumerous to omega (the set of natural numbers as ordinals). (Contributed by NM, 31-Jul-2004.) (Revised by Mario Carneiro, 15-Sep-2013.)
|- NN ~~ om
Theorem	nnct 10821	NN is dominated by om. (Contributed by Thierry Arnoux, 29-Dec-2016.)
|- NN ~<_ om
Theorem	uzennn 10822	An upper integer set is equinumerous to the set of natural numbers. (Contributed by Jim Kingdon, 30-Jul-2023.)
|- ( M e. ZZ -> ( ZZ>= ` M ) ~~ NN )
Theorem	xnn0nnen 10823	The set of extended nonnegative integers is equinumerous to the set of natural numbers. (Contributed by Jim Kingdon, 14-Jul-2025.)
|- NN0* ~~ NN
Theorem	fnn0nninf 10824*	A function from NN0 into ℕ∞. (Contributed by Jim Kingdon, 16-Jul-2022.)
|- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 )   &    |- F = ( n e. om |-> ( i e. om |-> if ( i e. n , 1o , (/) ) ) )   =>    |- ( F o. `' G ) : NN0 -->ℕ∞
Theorem	fxnn0nninf 10825*	A function from NN0* into ℕ∞. (Contributed by Jim Kingdon, 16-Jul-2022.) TODO: use infnninf 7428 instead of infnninfOLD 7429. More generally, this theorem and most theorems in this section could use an extended G defined by G = (frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 ) u. <. om , +oo >. ) and F = ( n e. suc om |-> ( i e. om |-> if ( i e. n , 1o , (/) ) ) ) as in nnnninf2 7431.
|- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 )   &    |- F = ( n e. om |-> ( i e. om |-> if ( i e. n , 1o , (/) ) ) )   &    |- I = ( ( F o. `' G ) u. { <. +oo , ( om X. { 1o } ) >. } )   =>    |- I :NN0* -->ℕ∞
Theorem	0tonninf 10826*	The mapping of zero into ℕ∞ is the sequence of all zeroes. (Contributed by Jim Kingdon, 17-Jul-2022.)
|- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 )   &    |- F = ( n e. om |-> ( i e. om |-> if ( i e. n , 1o , (/) ) ) )   &    |- I = ( ( F o. `' G ) u. { <. +oo , ( om X. { 1o } ) >. } )   =>    |- ( I ` 0 ) = ( x e. om |-> (/) )
Theorem	1tonninf 10827*	The mapping of one into ℕ∞ is a sequence which is a one followed by zeroes. (Contributed by Jim Kingdon, 17-Jul-2022.)
|- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 )   &    |- F = ( n e. om |-> ( i e. om |-> if ( i e. n , 1o , (/) ) ) )   &    |- I = ( ( F o. `' G ) u. { <. +oo , ( om X. { 1o } ) >. } )   =>    |- ( I ` 1 ) = ( x e. om |-> if ( x = (/) , 1o , (/) ) )
Theorem	inftonninf 10828*	The mapping of +oo into ℕ∞ is the sequence of all ones. (Contributed by Jim Kingdon, 17-Jul-2022.)
|- G = frec ( ( x e. ZZ |-> ( x + 1 ) ) , 0 )   &    |- F = ( n e. om |-> ( i e. om |-> if ( i e. n , 1o , (/) ) ) )   &    |- I = ( ( F o. `' G ) u. { <. +oo , ( om X. { 1o } ) >. } )   =>    |- ( I ` +oo ) = ( x e. om |-> 1o )
Theorem	nninfinf 10829	ℕ∞ is infinte. (Contributed by Jim Kingdon, 8-Jul-2025.)
|- om ~<_ ℕ∞
4.6.4  Strong induction over upper sets of integers
Theorem	uzsinds 10830*	Strong (or "total") induction principle over an upper set of integers. (Contributed by Scott Fenton, 16-May-2014.)
|- ( x = y -> ( ph <-> ps ) )   &    |- ( x = N -> ( ph <-> ch ) )   &    |- ( x e. ( ZZ>= ` M ) -> ( A. y e. ( M ... ( x - 1 ) ) ps -> ph ) )   =>    |- ( N e. ( ZZ>= ` M ) -> ch )
Theorem	nnsinds 10831*	Strong (or "total") induction principle over the naturals. (Contributed by Scott Fenton, 16-May-2014.)
|- ( x = y -> ( ph <-> ps ) )   &    |- ( x = N -> ( ph <-> ch ) )   &    |- ( x e. NN -> ( A. y e. ( 1 ... ( x - 1 ) ) ps -> ph ) )   =>    |- ( N e. NN -> ch )
Theorem	nn0sinds 10832*	Strong (or "total") induction principle over the nonnegative integers. (Contributed by Scott Fenton, 16-May-2014.)
|- ( x = y -> ( ph <-> ps ) )   &    |- ( x = N -> ( ph <-> ch ) )   &    |- ( x e. NN0 -> ( A. y e. ( 0 ... ( x - 1 ) ) ps -> ph ) )   =>    |- ( N e. NN0 -> ch )
4.6.5  The infinite sequence builder "seq"
Syntax	cseq 10833	Extend class notation with recursive sequence builder.
class seq M ( .+ , F )
Definition	df-seqfrec 10834*	Define a general-purpose operation that builds a recursive sequence (i.e., a function on an upper integer set such as NN or NN0) whose value at an index is a function of its previous value and the value of an input sequence at that index. This definition is complicated, but fortunately it is not intended to be used directly. Instead, the only purpose of this definition is to provide us with an object that has the properties expressed by seqf 10850, seq3-1 10848 and seq3p1 10851. Typically, those are the main theorems that would be used in practice. The first operand in the parentheses is the operation that is applied to the previous value and the value of the input sequence (second operand). The operand to the left of the parenthesis is the integer to start from. For example, for the operation +, an input sequence F with values 1, 1/2, 1/4, 1/8,... would be transformed into the output sequence seq 1 ( + , F ) with values 1, 3/2, 7/4, 15/8,.., so that ( seq 1 ( + , F ) ` 1 ) = 1, ( seq 1 ( + , F ) ` 2 ) = 3/2, etc. In other words, seq M ( + , F ) transforms a sequence F into an infinite series. seq M ( + , F ) ~~> 2 means "the sum of F(n) from n = M to infinity is 2". Since limits are unique (climuni 12003), by climdm 12005 the "sum of F(n) from n = 1 to infinity" can be expressed as ( ~~> ` seq 1 ( + , F ) ) (provided the sequence converges) and evaluates to 2 in this example. Internally, the frec function generates as its values a set of ordered pairs starting at <. M , ( F ` M ) >., with the first member of each pair incremented by one in each successive value. So, the range of frec is exactly the sequence we want, and we just extract the range and throw away the domain. (Contributed by NM, 18-Apr-2005.) (Revised by Jim Kingdon, 4-Nov-2022.)
|- seq M ( .+ , F ) = ran frec ( ( x e. ( ZZ>= ` M ) , y e. _V |-> <. ( x + 1 ) , ( y .+ ( F ` ( x + 1 ) ) ) >. ) , <. M , ( F ` M ) >. )
Theorem	seqex 10835	Existence of the sequence builder operation. (Contributed by Mario Carneiro, 4-Sep-2013.)
|- seq M ( .+ , F ) e. _V
Theorem	seqeq1 10836	Equality theorem for the sequence builder operation. (Contributed by Mario Carneiro, 4-Sep-2013.)
|- ( M = N -> seq M ( .+ , F ) = seq N ( .+ , F ) )
Theorem	seqeq2 10837	Equality theorem for the sequence builder operation. (Contributed by Mario Carneiro, 4-Sep-2013.)
|- ( .+ = Q -> seq M ( .+ , F ) = seq M ( Q , F ) )
Theorem	seqeq3 10838	Equality theorem for the sequence builder operation. (Contributed by Mario Carneiro, 4-Sep-2013.)
|- ( F = G -> seq M ( .+ , F ) = seq M ( .+ , G ) )
Theorem	seqeq1d 10839	Equality deduction for the sequence builder operation. (Contributed by Mario Carneiro, 7-Sep-2013.)
|- ( ph -> A = B )   =>    |- ( ph -> seq A ( .+ , F ) = seq B ( .+ , F ) )
Theorem	seqeq2d 10840	Equality deduction for the sequence builder operation. (Contributed by Mario Carneiro, 7-Sep-2013.)
|- ( ph -> A = B )   =>    |- ( ph -> seq M ( A , F ) = seq M ( B , F ) )
Theorem	seqeq3d 10841	Equality deduction for the sequence builder operation. (Contributed by Mario Carneiro, 7-Sep-2013.)
|- ( ph -> A = B )   =>    |- ( ph -> seq M ( .+ , A ) = seq M ( .+ , B ) )
Theorem	seqeq123d 10842	Equality deduction for the sequence builder operation. (Contributed by Mario Carneiro, 7-Sep-2013.)
|- ( ph -> M = N )   &    |- ( ph -> .+ = Q )   &    |- ( ph -> F = G )   =>    |- ( ph -> seq M ( .+ , F ) = seq N ( Q , G ) )
Theorem	nfseq 10843	Hypothesis builder for the sequence builder operation. (Contributed by Mario Carneiro, 24-Jun-2013.) (Revised by Mario Carneiro, 15-Oct-2016.)
|- F/_ x M   &    |- F/_ x .+   &    |- F/_ x F   =>    |- F/_ x seq M ( .+ , F )
Theorem	iseqovex 10844*	Closure of a function used in proving sequence builder theorems. This can be thought of as a lemma for the small number of sequence builder theorems which need it. (Contributed by Jim Kingdon, 31-May-2020.)
|- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ( ph /\ ( x e. ( ZZ>= ` M ) /\ y e. S ) ) -> ( x ( z e. ( ZZ>= ` M ) , w e. S |-> ( w .+ ( F ` ( z + 1 ) ) ) ) y ) e. S )
Theorem	iseqvalcbv 10845*	Changing the bound variables in an expression which appears in some seq related proofs. (Contributed by Jim Kingdon, 28-Apr-2022.)
|- frec ( ( x e. ( ZZ>= ` M ) , y e. T |-> <. ( x + 1 ) , ( x ( z e. ( ZZ>= ` M ) , w e. S |-> ( w .+ ( F ` ( z + 1 ) ) ) ) y ) >. ) , <. M , ( F ` M ) >. ) = frec ( ( a e. ( ZZ>= ` M ) , b e. T |-> <. ( a + 1 ) , ( a ( c e. ( ZZ>= ` M ) , d e. S |-> ( d .+ ( F ` ( c + 1 ) ) ) ) b ) >. ) , <. M , ( F ` M ) >. )
Theorem	seq3val 10846*	Value of the sequence builder function. This helps expand the definition although there should be little need for it once we have proved seqf 10850, seq3-1 10848 and seq3p1 10851, as further development can be done in terms of those. (Contributed by Mario Carneiro, 24-Jun-2013.) (Revised by Jim Kingdon, 4-Nov-2022.)
|- ( ph -> M e. ZZ )   &    |- R = frec ( ( x e. ( ZZ>= ` M ) , y e. _V |-> <. ( x + 1 ) , ( x ( z e. ( ZZ>= ` M ) , w e. S |-> ( w .+ ( F ` ( z + 1 ) ) ) ) y ) >. ) , <. M , ( F ` M ) >. )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ph -> seq M ( .+ , F ) = ran R )
Theorem	seqvalcd 10847*	Value of the sequence builder function. Similar to seq3val 10846 but the classes D (type of each term) and C (type of the value we are accumulating) do not need to be the same. (Contributed by Jim Kingdon, 9-Jul-2023.)
|- ( ph -> M e. ZZ )   &    |- R = frec ( ( x e. ( ZZ>= ` M ) , y e. _V |-> <. ( x + 1 ) , ( x ( z e. ( ZZ>= ` M ) , w e. C |-> ( w .+ ( F ` ( z + 1 ) ) ) ) y ) >. ) , <. M , ( F ` M ) >. )   &    |- ( ph -> ( F ` M ) e. C )   &    |- ( ( ph /\ ( x e. C /\ y e. D ) ) -> ( x .+ y ) e. C )   &    |- ( ( ph /\ x e. ( ZZ>= ` ( M + 1 ) ) ) -> ( F ` x ) e. D )   =>    |- ( ph -> seq M ( .+ , F ) = ran R )
Theorem	seq3-1 10848*	Value of the sequence builder function at its initial value. (Contributed by Jim Kingdon, 3-Oct-2022.)
|- ( ph -> M e. ZZ )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ph -> ( seq M ( .+ , F ) ` M ) = ( F ` M ) )
Theorem	seq1g 10849	Value of the sequence builder function at its initial value. (Contributed by Mario Carneiro, 24-Jun-2013.) (Revised by Jim Kingdon, 19-Aug-2025.)
|- ( ( M e. ZZ /\ F e. V /\ .+ e. W ) -> ( seq M ( .+ , F ) ` M ) = ( F ` M ) )
Theorem	seqf 10850*	Range of the recursive sequence builder. (Contributed by Mario Carneiro, 24-Jun-2013.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ x e. Z ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ph -> seq M ( .+ , F ) : Z --> S )
Theorem	seq3p1 10851*	Value of the sequence builder function at a successor. (Contributed by Jim Kingdon, 30-Apr-2022.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ph -> ( seq M ( .+ , F ) ` ( N + 1 ) ) = ( ( seq M ( .+ , F ) ` N ) .+ ( F ` ( N + 1 ) ) ) )
Theorem	seqp1g 10852	Value of the sequence builder function at a successor. (Contributed by Mario Carneiro, 24-Jun-2013.) (Revised by Jim Kingdon, 19-Aug-2025.)
|- ( ( N e. ( ZZ>= ` M ) /\ F e. V /\ .+ e. W ) -> ( seq M ( .+ , F ) ` ( N + 1 ) ) = ( ( seq M ( .+ , F ) ` N ) .+ ( F ` ( N + 1 ) ) ) )
Theorem	seqovcd 10853*	A closure law for the recursive sequence builder. This is a lemma for theorems such as seqf2 10854 and seq1cd 10855 and is unlikely to be needed once such theorems are proved. (Contributed by Jim Kingdon, 20-Jul-2023.)
|- ( ( ph /\ x e. ( ZZ>= ` ( M + 1 ) ) ) -> ( F ` x ) e. D )   &    |- ( ( ph /\ ( x e. C /\ y e. D ) ) -> ( x .+ y ) e. C )   =>    |- ( ( ph /\ ( x e. ( ZZ>= ` M ) /\ y e. C ) ) -> ( x ( z e. ( ZZ>= ` M ) , w e. C |-> ( w .+ ( F ` ( z + 1 ) ) ) ) y ) e. C )
Theorem	seqf2 10854*	Range of the recursive sequence builder. (Contributed by Mario Carneiro, 24-Jun-2013.) (Revised by Jim Kingdon, 7-Jul-2023.)
|- ( ph -> ( F ` M ) e. C )   &    |- ( ( ph /\ ( x e. C /\ y e. D ) ) -> ( x .+ y ) e. C )   &    |- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ x e. ( ZZ>= ` ( M + 1 ) ) ) -> ( F ` x ) e. D )   =>    |- ( ph -> seq M ( .+ , F ) : Z --> C )
Theorem	seq1cd 10855*	Initial value of the recursive sequence builder. A version of seq3-1 10848 which provides two classes D and C for the terms and the value being accumulated, respectively. (Contributed by Jim Kingdon, 19-Jul-2023.)
|- ( ph -> ( F ` M ) e. C )   &    |- ( ( ph /\ ( x e. C /\ y e. D ) ) -> ( x .+ y ) e. C )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ x e. ( ZZ>= ` ( M + 1 ) ) ) -> ( F ` x ) e. D )   =>    |- ( ph -> ( seq M ( .+ , F ) ` M ) = ( F ` M ) )
Theorem	seqp1cd 10856*	Value of the sequence builder function at a successor. A version of seq3p1 10851 which provides two classes D and C for the terms and the value being accumulated, respectively. (Contributed by Jim Kingdon, 20-Jul-2023.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> ( F ` M ) e. C )   &    |- ( ( ph /\ ( x e. C /\ y e. D ) ) -> ( x .+ y ) e. C )   &    |- ( ( ph /\ x e. ( ZZ>= ` ( M + 1 ) ) ) -> ( F ` x ) e. D )   =>    |- ( ph -> ( seq M ( .+ , F ) ` ( N + 1 ) ) = ( ( seq M ( .+ , F ) ` N ) .+ ( F ` ( N + 1 ) ) ) )
Theorem	seq3clss 10857*	Closure property of the recursive sequence builder. (Contributed by Jim Kingdon, 28-Sep-2022.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. T )   &    |- ( ( ph /\ x e. ( M ... N ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ph -> S C_ T )   &    |- ( ( ph /\ ( x e. T /\ y e. T ) ) -> ( x .+ y ) e. T )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) e. S )
Theorem	seqclg 10858*	Closure properties of the recursive sequence builder. (Contributed by Mario Carneiro, 2-Jul-2013.) (Revised by Mario Carneiro, 27-May-2014.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ x e. ( M ... N ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ph -> F e. V )   &    |- ( ph -> .+ e. W )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) e. S )
Theorem	seq3m1 10859*	Value of the sequence builder function at a successor. (Contributed by Mario Carneiro, 24-Jun-2013.) (Revised by Jim Kingdon, 3-Nov-2022.)
|- ( ph -> M e. ZZ )   &    |- ( ph -> N e. ( ZZ>= ` ( M + 1 ) ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( ( seq M ( .+ , F ) ` ( N - 1 ) ) .+ ( F ` N ) ) )
Theorem	seqm1g 10860	Value of the sequence builder function at a successor. (Contributed by Mario Carneiro, 24-Jun-2013.) (Revised by Jim Kingdon, 30-Aug-2025.)
|- ( ph -> M e. ZZ )   &    |- ( ph -> N e. ( ZZ>= ` ( M + 1 ) ) )   &    |- ( ph -> .+ e. V )   &    |- ( ph -> F e. W )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( ( seq M ( .+ , F ) ` ( N - 1 ) ) .+ ( F ` N ) ) )
Theorem	seq3fveq2 10861*	Equality of sequences. (Contributed by Jim Kingdon, 3-Jun-2020.)
|- ( ph -> K e. ( ZZ>= ` M ) )   &    |- ( ph -> ( seq M ( .+ , F ) ` K ) = ( G ` K ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ x e. ( ZZ>= ` K ) ) -> ( G ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ph -> N e. ( ZZ>= ` K ) )   &    |- ( ( ph /\ k e. ( ( K + 1 ) ... N ) ) -> ( F ` k ) = ( G ` k ) )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( seq K ( .+ , G ) ` N ) )
Theorem	seq3feq2 10862*	Equality of sequences. (Contributed by Jim Kingdon, 3-Jun-2020.)
|- ( ph -> K e. ( ZZ>= ` M ) )   &    |- ( ph -> ( seq M ( .+ , F ) ` K ) = ( G ` K ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ x e. ( ZZ>= ` K ) ) -> ( G ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ k e. ( ZZ>= ` ( K + 1 ) ) ) -> ( F ` k ) = ( G ` k ) )   =>    |- ( ph -> ( seq M ( .+ , F ) |` ( ZZ>= ` K ) ) = seq K ( .+ , G ) )
Theorem	seqfveq2g 10863*	Equality of sequences. (Contributed by NM, 17-Mar-2005.) (Revised by Mario Carneiro, 27-May-2014.)
|- ( ph -> K e. ( ZZ>= ` M ) )   &    |- ( ph -> ( seq M ( .+ , F ) ` K ) = ( G ` K ) )   &    |- ( ph -> .+ e. V )   &    |- ( ph -> F e. W )   &    |- ( ph -> G e. X )   &    |- ( ph -> N e. ( ZZ>= ` K ) )   &    |- ( ( ph /\ k e. ( ( K + 1 ) ... N ) ) -> ( F ` k ) = ( G ` k ) )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( seq K ( .+ , G ) ` N ) )
Theorem	seqfveqg 10864*	Equality of sequences. (Contributed by NM, 17-Mar-2005.) (Revised by Mario Carneiro, 27-May-2014.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) = ( G ` k ) )   &    |- ( ph -> .+ e. V )   &    |- ( ph -> F e. W )   &    |- ( ph -> G e. X )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( seq M ( .+ , G ) ` N ) )
Theorem	seq3fveq 10865*	Equality of sequences. (Contributed by Jim Kingdon, 4-Jun-2020.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) = ( G ` k ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( G ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( seq M ( .+ , G ) ` N ) )
Theorem	seq3feq 10866*	Equality of sequences. (Contributed by Jim Kingdon, 15-Aug-2021.) (Revised by Jim Kingdon, 7-Apr-2023.)
|- ( ph -> M e. ZZ )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( F ` k ) = ( G ` k ) )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ph -> seq M ( .+ , F ) = seq M ( .+ , G ) )
Theorem	seq3shft2 10867*	Shifting the index set of a sequence. (Contributed by Jim Kingdon, 15-Aug-2021.) (Revised by Jim Kingdon, 7-Apr-2023.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> K e. ZZ )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) = ( G ` ( k + K ) ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   &    |- ( ( ph /\ x e. ( ZZ>= ` ( M + K ) ) ) -> ( G ` x ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( seq ( M + K ) ( .+ , G ) ` ( N + K ) ) )
Theorem	seqshft2g 10868*	Shifting the index set of a sequence. (Contributed by Mario Carneiro, 27-Feb-2014.) (Revised by Mario Carneiro, 27-May-2014.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> K e. ZZ )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) = ( G ` ( k + K ) ) )   &    |- ( ph -> .+ e. V )   &    |- ( ph -> F e. W )   &    |- ( ph -> G e. X )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( seq ( M + K ) ( .+ , G ) ` ( N + K ) ) )
Theorem	serf 10869*	An infinite series of complex terms is a function from NN to CC. (Contributed by NM, 18-Apr-2005.) (Revised by Mario Carneiro, 27-May-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) e. CC )   =>    |- ( ph -> seq M ( + , F ) : Z --> CC )
Theorem	serfre 10870*	An infinite series of real numbers is a function from NN to RR. (Contributed by NM, 18-Apr-2005.) (Revised by Mario Carneiro, 27-May-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) e. RR )   =>    |- ( ph -> seq M ( + , F ) : Z --> RR )
Theorem	monoord 10871*	Ordering relation for a monotonic sequence, increasing case. (Contributed by NM, 13-Mar-2005.) (Revised by Mario Carneiro, 9-Feb-2014.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) e. RR )   &    |- ( ( ph /\ k e. ( M ... ( N - 1 ) ) ) -> ( F ` k ) <_ ( F ` ( k + 1 ) ) )   =>    |- ( ph -> ( F ` M ) <_ ( F ` N ) )
Theorem	monoord2 10872*	Ordering relation for a monotonic sequence, decreasing case. (Contributed by Mario Carneiro, 18-Jul-2014.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) e. RR )   &    |- ( ( ph /\ k e. ( M ... ( N - 1 ) ) ) -> ( F ` ( k + 1 ) ) <_ ( F ` k ) )   =>    |- ( ph -> ( F ` N ) <_ ( F ` M ) )
Theorem	ser3mono 10873*	The partial sums in an infinite series of positive terms form a monotonic sequence. (Contributed by NM, 17-Mar-2005.) (Revised by Jim Kingdon, 22-Apr-2023.)
|- ( ph -> K e. ( ZZ>= ` M ) )   &    |- ( ph -> N e. ( ZZ>= ` K ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. RR )   &    |- ( ( ph /\ x e. ( ( K + 1 ) ... N ) ) -> 0 <_ ( F ` x ) )   =>    |- ( ph -> ( seq M ( + , F ) ` K ) <_ ( seq M ( + , F ) ` N ) )
Theorem	seq3split 10874*	Split a sequence into two sequences. (Contributed by Jim Kingdon, 16-Aug-2021.) (Revised by Jim Kingdon, 21-Oct-2022.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` ( M + 1 ) ) )   &    |- ( ph -> M e. ( ZZ>= ` K ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` K ) ) -> ( F ` x ) e. S )   =>    |- ( ph -> ( seq K ( .+ , F ) ` N ) = ( ( seq K ( .+ , F ) ` M ) .+ ( seq ( M + 1 ) ( .+ , F ) ` N ) ) )
Theorem	seqsplitg 10875*	Split a sequence into two sequences. (Contributed by NM, 17-Mar-2005.) (Revised by Mario Carneiro, 27-May-2014.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` ( M + 1 ) ) )   &    |- ( ph -> .+ e. V )   &    |- ( ph -> F e. W )   &    |- ( ph -> M e. ( ZZ>= ` K ) )   &    |- ( ( ph /\ x e. ( K ... N ) ) -> ( F ` x ) e. S )   =>    |- ( ph -> ( seq K ( .+ , F ) ` N ) = ( ( seq K ( .+ , F ) ` M ) .+ ( seq ( M + 1 ) ( .+ , F ) ` N ) ) )
Theorem	seq3-1p 10876*	Removing the first term from a sequence. (Contributed by Jim Kingdon, 16-Aug-2021.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` ( M + 1 ) ) )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( F ` x ) e. S )   =>    |- ( ph -> ( seq M ( .+ , F ) ` N ) = ( ( F ` M ) .+ ( seq ( M + 1 ) ( .+ , F ) ` N ) ) )
Theorem	seq3caopr3 10877*	Lemma for seq3caopr2 10879. (Contributed by Mario Carneiro, 25-Apr-2016.) (Revised by Jim Kingdon, 22-Apr-2023.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x Q y ) e. S )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( F ` k ) e. S )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( G ` k ) e. S )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( H ` k ) = ( ( F ` k ) Q ( G ` k ) ) )   &    |- ( ( ph /\ n e. ( M..^ N ) ) -> ( ( ( seq M ( .+ , F ) ` n ) Q ( seq M ( .+ , G ) ` n ) ) .+ ( ( F ` ( n + 1 ) ) Q ( G ` ( n + 1 ) ) ) ) = ( ( ( seq M ( .+ , F ) ` n ) .+ ( F ` ( n + 1 ) ) ) Q ( ( seq M ( .+ , G ) ` n ) .+ ( G ` ( n + 1 ) ) ) ) )   =>    |- ( ph -> ( seq M ( .+ , H ) ` N ) = ( ( seq M ( .+ , F ) ` N ) Q ( seq M ( .+ , G ) ` N ) ) )
Theorem	seqcaopr3g 10878*	Lemma for seqcaopr2g 10880. (Contributed by Mario Carneiro, 25-Apr-2016.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x Q y ) e. S )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) e. S )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( G ` k ) e. S )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( H ` k ) = ( ( F ` k ) Q ( G ` k ) ) )   &    |- ( ph -> .+ e. V )   &    |- ( ph -> F e. W )   &    |- ( ph -> G e. X )   &    |- ( ph -> H e. Y )   &    |- ( ( ph /\ n e. ( M..^ N ) ) -> ( ( ( seq M ( .+ , F ) ` n ) Q ( seq M ( .+ , G ) ` n ) ) .+ ( ( F ` ( n + 1 ) ) Q ( G ` ( n + 1 ) ) ) ) = ( ( ( seq M ( .+ , F ) ` n ) .+ ( F ` ( n + 1 ) ) ) Q ( ( seq M ( .+ , G ) ` n ) .+ ( G ` ( n + 1 ) ) ) ) )   =>    |- ( ph -> ( seq M ( .+ , H ) ` N ) = ( ( seq M ( .+ , F ) ` N ) Q ( seq M ( .+ , G ) ` N ) ) )
Theorem	seq3caopr2 10879*	The sum of two infinite series (generalized to an arbitrary commutative and associative operation). (Contributed by Mario Carneiro, 30-May-2014.) (Revised by Jim Kingdon, 23-Apr-2023.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x Q y ) e. S )   &    |- ( ( ph /\ ( ( x e. S /\ y e. S ) /\ ( z e. S /\ w e. S ) ) ) -> ( ( x Q z ) .+ ( y Q w ) ) = ( ( x .+ y ) Q ( z .+ w ) ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( F ` k ) e. S )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( G ` k ) e. S )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( H ` k ) = ( ( F ` k ) Q ( G ` k ) ) )   =>    |- ( ph -> ( seq M ( .+ , H ) ` N ) = ( ( seq M ( .+ , F ) ` N ) Q ( seq M ( .+ , G ) ` N ) ) )
Theorem	seqcaopr2g 10880*	The sum of two infinite series (generalized to an arbitrary commutative and associative operation). (Contributed by Mario Carneiro, 30-May-2014.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x Q y ) e. S )   &    |- ( ( ph /\ ( ( x e. S /\ y e. S ) /\ ( z e. S /\ w e. S ) ) ) -> ( ( x Q z ) .+ ( y Q w ) ) = ( ( x .+ y ) Q ( z .+ w ) ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) e. S )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( G ` k ) e. S )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( H ` k ) = ( ( F ` k ) Q ( G ` k ) ) )   &    |- ( ph -> .+ e. V )   &    |- ( ph -> F e. W )   &    |- ( ph -> G e. X )   &    |- ( ph -> H e. Y )   =>    |- ( ph -> ( seq M ( .+ , H ) ` N ) = ( ( seq M ( .+ , F ) ` N ) Q ( seq M ( .+ , G ) ` N ) ) )
Theorem	seq3caopr 10881*	The sum of two infinite series (generalized to an arbitrary commutative and associative operation). (Contributed by NM, 17-Mar-2005.) (Revised by Jim Kingdon, 23-Apr-2023.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) = ( y .+ x ) )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( F ` k ) e. S )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( G ` k ) e. S )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( H ` k ) = ( ( F ` k ) .+ ( G ` k ) ) )   =>    |- ( ph -> ( seq M ( .+ , H ) ` N ) = ( ( seq M ( .+ , F ) ` N ) .+ ( seq M ( .+ , G ) ` N ) ) )
Theorem	seqcaoprg 10882*	The sum of two infinite series (generalized to an arbitrary commutative and associative operation). (Contributed by NM, 17-Mar-2005.) (Revised by Mario Carneiro, 30-May-2014.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) = ( y .+ x ) )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( F ` k ) e. S )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( G ` k ) e. S )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> ( H ` k ) = ( ( F ` k ) .+ ( G ` k ) ) )   &    |- ( ph -> .+ e. V )   &    |- ( ph -> F e. W )   &    |- ( ph -> G e. X )   &    |- ( ph -> H e. Y )   =>    |- ( ph -> ( seq M ( .+ , H ) ` N ) = ( ( seq M ( .+ , F ) ` N ) .+ ( seq M ( .+ , G ) ` N ) ) )
Theorem	iseqf1olemkle 10883*	Lemma for seq3f1o 10903. (Contributed by Jim Kingdon, 21-Aug-2022.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A. x e. ( M..^ K ) ( J ` x ) = x )   =>    |- ( ph -> K <_ ( `' J ` K ) )
Theorem	iseqf1olemklt 10884*	Lemma for seq3f1o 10903. (Contributed by Jim Kingdon, 21-Aug-2022.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A. x e. ( M..^ K ) ( J ` x ) = x )   &    |- ( ph -> K =/= ( `' J ` K ) )   =>    |- ( ph -> K < ( `' J ` K ) )
Theorem	iseqf1olemqcl 10885	Lemma for seq3f1o 10903. (Contributed by Jim Kingdon, 27-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A e. ( M ... N ) )   =>    |- ( ph -> if ( A e. ( K ... ( `' J ` K ) ) , if ( A = K , K , ( J ` ( A - 1 ) ) ) , ( J ` A ) ) e. ( M ... N ) )
Theorem	iseqf1olemqval 10886*	Lemma for seq3f1o 10903. Value of the function Q. (Contributed by Jim Kingdon, 28-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A e. ( M ... N ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   =>    |- ( ph -> ( Q ` A ) = if ( A e. ( K ... ( `' J ` K ) ) , if ( A = K , K , ( J ` ( A - 1 ) ) ) , ( J ` A ) ) )
Theorem	iseqf1olemnab 10887*	Lemma for seq3f1o 10903. (Contributed by Jim Kingdon, 27-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A e. ( M ... N ) )   &    |- ( ph -> B e. ( M ... N ) )   &    |- ( ph -> ( Q ` A ) = ( Q ` B ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   =>    |- ( ph -> -. ( A e. ( K ... ( `' J ` K ) ) /\ -. B e. ( K ... ( `' J ` K ) ) ) )
Theorem	iseqf1olemab 10888*	Lemma for seq3f1o 10903. (Contributed by Jim Kingdon, 27-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A e. ( M ... N ) )   &    |- ( ph -> B e. ( M ... N ) )   &    |- ( ph -> ( Q ` A ) = ( Q ` B ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- ( ph -> A e. ( K ... ( `' J ` K ) ) )   &    |- ( ph -> B e. ( K ... ( `' J ` K ) ) )   =>    |- ( ph -> A = B )
Theorem	iseqf1olemnanb 10889*	Lemma for seq3f1o 10903. (Contributed by Jim Kingdon, 27-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A e. ( M ... N ) )   &    |- ( ph -> B e. ( M ... N ) )   &    |- ( ph -> ( Q ` A ) = ( Q ` B ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- ( ph -> -. A e. ( K ... ( `' J ` K ) ) )   &    |- ( ph -> -. B e. ( K ... ( `' J ` K ) ) )   =>    |- ( ph -> A = B )
Theorem	iseqf1olemqf 10890*	Lemma for seq3f1o 10903. Domain and codomain of Q. (Contributed by Jim Kingdon, 26-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   =>    |- ( ph -> Q : ( M ... N ) --> ( M ... N ) )
Theorem	iseqf1olemmo 10891*	Lemma for seq3f1o 10903. Showing that Q is one-to-one. (Contributed by Jim Kingdon, 27-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- ( ph -> A e. ( M ... N ) )   &    |- ( ph -> B e. ( M ... N ) )   &    |- ( ph -> ( Q ` A ) = ( Q ` B ) )   =>    |- ( ph -> A = B )
Theorem	iseqf1olemqf1o 10892*	Lemma for seq3f1o 10903. Q is a permutation of ( M ... N ). Q is formed from the constant portion of J, followed by the single element K (at position K), followed by the rest of J (with the K deleted and the elements before K moved one position later to fill the gap). (Contributed by Jim Kingdon, 21-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   =>    |- ( ph -> Q : ( M ... N ) -1-1-onto-> ( M ... N ) )
Theorem	iseqf1olemqk 10893*	Lemma for seq3f1o 10903. Q is constant for one more position than J is. (Contributed by Jim Kingdon, 21-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- ( ph -> A. x e. ( M..^ K ) ( J ` x ) = x )   =>    |- ( ph -> A. x e. ( M ... K ) ( Q ` x ) = x )
Theorem	iseqf1olemjpcl 10894*	Lemma for seq3f1o 10903. A closure lemma involving J and P. (Contributed by Jim Kingdon, 29-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( G ` x ) e. S )   &    |- P = ( x e. ( ZZ>= ` M ) |-> if ( x <_ N , ( G ` ( f ` x ) ) , ( G ` M ) ) )   =>    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( [_ J / f ]_ P ` x ) e. S )
Theorem	iseqf1olemqpcl 10895*	Lemma for seq3f1o 10903. A closure lemma involving Q and P. (Contributed by Jim Kingdon, 29-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( G ` x ) e. S )   &    |- P = ( x e. ( ZZ>= ` M ) |-> if ( x <_ N , ( G ` ( f ` x ) ) , ( G ` M ) ) )   =>    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( [_ Q / f ]_ P ` x ) e. S )
Theorem	iseqf1olemfvp 10896*	Lemma for seq3f1o 10903. (Contributed by Jim Kingdon, 30-Aug-2022.)
|- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> T : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A e. ( M ... N ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( G ` x ) e. S )   &    |- P = ( x e. ( ZZ>= ` M ) |-> if ( x <_ N , ( G ` ( f ` x ) ) , ( G ` M ) ) )   =>    |- ( ph -> ( [_ T / f ]_ P ` A ) = ( G ` ( T ` A ) ) )
Theorem	seq3f1olemqsumkj 10897*	Lemma for seq3f1o 10903. Q gives the same sum as J in the range ( K ... ( `' J ` K ) ). (Contributed by Jim Kingdon, 29-Aug-2022.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) = ( y .+ x ) )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> F : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( G ` x ) e. S )   &    |- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A. x e. ( M..^ K ) ( J ` x ) = x )   &    |- ( ph -> K =/= ( `' J ` K ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- P = ( x e. ( ZZ>= ` M ) |-> if ( x <_ N , ( G ` ( f ` x ) ) , ( G ` M ) ) )   =>    |- ( ph -> ( seq K ( .+ , [_ J / f ]_ P ) ` ( `' J ` K ) ) = ( seq K ( .+ , [_ Q / f ]_ P ) ` ( `' J ` K ) ) )
Theorem	seq3f1olemqsumk 10898*	Lemma for seq3f1o 10903. Q gives the same sum as J in the range ( K ... N ). (Contributed by Jim Kingdon, 22-Aug-2022.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) = ( y .+ x ) )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> F : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( G ` x ) e. S )   &    |- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A. x e. ( M..^ K ) ( J ` x ) = x )   &    |- ( ph -> K =/= ( `' J ` K ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- P = ( x e. ( ZZ>= ` M ) |-> if ( x <_ N , ( G ` ( f ` x ) ) , ( G ` M ) ) )   =>    |- ( ph -> ( seq K ( .+ , [_ J / f ]_ P ) ` N ) = ( seq K ( .+ , [_ Q / f ]_ P ) ` N ) )
Theorem	seq3f1olemqsum 10899*	Lemma for seq3f1o 10903. Q gives the same sum as J. (Contributed by Jim Kingdon, 21-Aug-2022.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) = ( y .+ x ) )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> F : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( G ` x ) e. S )   &    |- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A. x e. ( M..^ K ) ( J ` x ) = x )   &    |- ( ph -> K =/= ( `' J ` K ) )   &    |- Q = ( u e. ( M ... N ) |-> if ( u e. ( K ... ( `' J ` K ) ) , if ( u = K , K , ( J ` ( u - 1 ) ) ) , ( J ` u ) ) )   &    |- P = ( x e. ( ZZ>= ` M ) |-> if ( x <_ N , ( G ` ( f ` x ) ) , ( G ` M ) ) )   =>    |- ( ph -> ( seq M ( .+ , [_ J / f ]_ P ) ` N ) = ( seq M ( .+ , [_ Q / f ]_ P ) ` N ) )
Theorem	seq3f1olemstep 10900*	Lemma for seq3f1o 10903. Given a permutation which is constant up to a point, supply a new one which is constant for one more position. (Contributed by Jim Kingdon, 19-Aug-2022.)
|- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) e. S )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x .+ y ) = ( y .+ x ) )   &    |- ( ( ph /\ ( x e. S /\ y e. S /\ z e. S ) ) -> ( ( x .+ y ) .+ z ) = ( x .+ ( y .+ z ) ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ph -> F : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ( ph /\ x e. ( ZZ>= ` M ) ) -> ( G ` x ) e. S )   &    |- ( ph -> K e. ( M ... N ) )   &    |- ( ph -> J : ( M ... N ) -1-1-onto-> ( M ... N ) )   &    |- ( ph -> A. x e. ( M..^ K ) ( J ` x ) = x )   &    |- ( ph -> ( seq M ( .+ , [_ J / f ]_ P ) ` N ) = ( seq M ( .+ , L ) ` N ) )   &    |- P = ( x e. ( ZZ>= ` M ) |-> if ( x <_ N , ( G ` ( f ` x ) ) , ( G ` M ) ) )   =>    |- ( ph -> E. f ( f : ( M ... N ) -1-1-onto-> ( M ... N ) /\ A. x e. ( M ... K ) ( f ` x ) = x /\ ( seq M ( .+ , P ) ` N ) = ( seq M ( .+ , L ) ` N ) ) )