P. 115 of Theorem List - Intuitionistic Logic Explorer

Theorem List for Intuitionistic Logic Explorer - 11401-11500   *Has distinct variable group(s)

Type	Label	Description
Statement
Theorem	isumss 11401*	Change the index set to a subset in an upper integer sum. (Contributed by Mario Carneiro, 21-Apr-2014.) (Revised by Jim Kingdon, 21-Sep-2022.)
|- ( ph -> A C_ B )   &    |- ( ( ph /\ k e. A ) -> C e. CC )   &    |- ( ( ph /\ k e. ( B \ A ) ) -> C = 0 )   &    |- ( ph -> A. j e. ( ZZ>= ` M )DECID j e. A )   &    |- ( ph -> M e. ZZ )   &    |- ( ph -> B C_ ( ZZ>= ` M ) )   &    |- ( ph -> A. j e. ( ZZ>= ` M )DECID j e. B )   =>    |- ( ph -> sum_ k e. A C = sum_ k e. B C )
Theorem	fisumss 11402*	Change the index set to a subset in a finite sum. (Contributed by Mario Carneiro, 21-Apr-2014.) (Revised by Jim Kingdon, 23-Sep-2022.)
|- ( ph -> A C_ B )   &    |- ( ( ph /\ k e. A ) -> C e. CC )   &    |- ( ( ph /\ k e. ( B \ A ) ) -> C = 0 )   &    |- ( ph -> A. j e. B DECID j e. A )   &    |- ( ph -> B e. Fin )   =>    |- ( ph -> sum_ k e. A C = sum_ k e. B C )
Theorem	isumss2 11403*	Change the index set of a sum by adding zeroes. The nonzero elements are in the contained set A and the added zeroes compose the rest of the containing set B which needs to be summable. (Contributed by Mario Carneiro, 15-Jul-2013.) (Revised by Jim Kingdon, 24-Sep-2022.)
|- ( ph -> A C_ B )   &    |- ( ph -> A. j e. B DECID j e. A )   &    |- ( ph -> A. k e. A C e. CC )   &    |- ( ph -> ( ( M e. ZZ /\ B C_ ( ZZ>= ` M ) /\ A. j e. ( ZZ>= ` M )DECID j e. B ) \/ B e. Fin ) )   =>    |- ( ph -> sum_ k e. A C = sum_ k e. B if ( k e. A , C , 0 ) )
Theorem	fsum3cvg2 11404*	The sequence of partial sums of a finite sum converges to the whole sum. (Contributed by Mario Carneiro, 20-Apr-2014.) (Revised by Jim Kingdon, 2-Dec-2022.)
|- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( F ` k ) = if ( k e. A , B , 0 ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> DECID k e. A )   &    |- ( ph -> A C_ ( M ... N ) )   =>    |- ( ph -> seq M ( + , F ) ~~> ( seq M ( + , F ) ` N ) )
Theorem	fsumsersdc 11405*	Special case of series sum over a finite upper integer index set. (Contributed by Mario Carneiro, 26-Jul-2013.) (Revised by Jim Kingdon, 5-May-2023.)
|- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( F ` k ) = if ( k e. A , B , 0 ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> DECID k e. A )   &    |- ( ph -> A C_ ( M ... N ) )   =>    |- ( ph -> sum_ k e. A B = ( seq M ( + , F ) ` N ) )
Theorem	fsum3cvg3 11406*	A finite sum is convergent. (Contributed by Mario Carneiro, 24-Apr-2014.) (Revised by Jim Kingdon, 2-Dec-2022.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ph -> A e. Fin )   &    |- ( ph -> A C_ Z )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> DECID k e. A )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = if ( k e. A , B , 0 ) )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> seq M ( + , F ) e. dom ~~> )
Theorem	fsum3ser 11407*	A finite sum expressed in terms of a partial sum of an infinite series. The recursive definition follows as fsum1 11422 and fsump1 11430, which should make our notation clear and from which, along with closure fsumcl 11410, we will derive the basic properties of finite sums. (Contributed by NM, 11-Dec-2005.) (Revised by Jim Kingdon, 1-Oct-2022.)
|- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> ( F ` k ) = A )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( ZZ>= ` M ) ) -> A e. CC )   =>    |- ( ph -> sum_ k e. ( M ... N ) A = ( seq M ( + , F ) ` N ) )
Theorem	fsumcl2lem 11408*	- Lemma for finite sum closures. (The "-" before "Lemma" forces the math content to be displayed in the Statement List - NM 11-Feb-2008.) (Contributed by Mario Carneiro, 3-Jun-2014.)
|- ( ph -> S C_ CC )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x + y ) e. S )   &    |- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. S )   &    |- ( ph -> A =/= (/) )   =>    |- ( ph -> sum_ k e. A B e. S )
Theorem	fsumcllem 11409*	- Lemma for finite sum closures. (The "-" before "Lemma" forces the math content to be displayed in the Statement List - NM 11-Feb-2008.) (Contributed by NM, 9-Nov-2005.) (Revised by Mario Carneiro, 3-Jun-2014.)
|- ( ph -> S C_ CC )   &    |- ( ( ph /\ ( x e. S /\ y e. S ) ) -> ( x + y ) e. S )   &    |- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. S )   &    |- ( ph -> 0 e. S )   =>    |- ( ph -> sum_ k e. A B e. S )
Theorem	fsumcl 11410*	Closure of a finite sum of complex numbers A ( k ). (Contributed by NM, 9-Nov-2005.) (Revised by Mario Carneiro, 22-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> sum_ k e. A B e. CC )
Theorem	fsumrecl 11411*	Closure of a finite sum of reals. (Contributed by NM, 9-Nov-2005.) (Revised by Mario Carneiro, 22-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. RR )   =>    |- ( ph -> sum_ k e. A B e. RR )
Theorem	fsumzcl 11412*	Closure of a finite sum of integers. (Contributed by NM, 9-Nov-2005.) (Revised by Mario Carneiro, 22-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. ZZ )   =>    |- ( ph -> sum_ k e. A B e. ZZ )
Theorem	fsumnn0cl 11413*	Closure of a finite sum of nonnegative integers. (Contributed by Mario Carneiro, 23-Apr-2015.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. NN0 )   =>    |- ( ph -> sum_ k e. A B e. NN0 )
Theorem	fsumrpcl 11414*	Closure of a finite sum of positive reals. (Contributed by Mario Carneiro, 3-Jun-2014.)
|- ( ph -> A e. Fin )   &    |- ( ph -> A =/= (/) )   &    |- ( ( ph /\ k e. A ) -> B e. RR+ )   =>    |- ( ph -> sum_ k e. A B e. RR+ )
Theorem	fsumzcl2 11415*	A finite sum with integer summands is an integer. (Contributed by Alexander van der Vekens, 31-Aug-2018.)
|- ( ( A e. Fin /\ A. k e. A B e. ZZ ) -> sum_ k e. A B e. ZZ )
Theorem	fsumadd 11416*	The sum of two finite sums. (Contributed by NM, 14-Nov-2005.) (Revised by Mario Carneiro, 22-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   &    |- ( ( ph /\ k e. A ) -> C e. CC )   =>    |- ( ph -> sum_ k e. A ( B + C ) = ( sum_ k e. A B + sum_ k e. A C ) )
Theorem	fsumsplit 11417*	Split a sum into two parts. (Contributed by Mario Carneiro, 18-Aug-2013.) (Revised by Mario Carneiro, 22-Apr-2014.)
|- ( ph -> ( A i^i B ) = (/) )   &    |- ( ph -> U = ( A u. B ) )   &    |- ( ph -> U e. Fin )   &    |- ( ( ph /\ k e. U ) -> C e. CC )   =>    |- ( ph -> sum_ k e. U C = ( sum_ k e. A C + sum_ k e. B C ) )
Theorem	fsumsplitf 11418*	Split a sum into two parts. A version of fsumsplit 11417 using bound-variable hypotheses instead of distinct variable conditions. (Contributed by Glauco Siliprandi, 5-Apr-2020.)
|- F/ k ph   &    |- ( ph -> ( A i^i B ) = (/) )   &    |- ( ph -> U = ( A u. B ) )   &    |- ( ph -> U e. Fin )   &    |- ( ( ph /\ k e. U ) -> C e. CC )   =>    |- ( ph -> sum_ k e. U C = ( sum_ k e. A C + sum_ k e. B C ) )
Theorem	sumsnf 11419*	A sum of a singleton is the term. A version of sumsn 11421 using bound-variable hypotheses instead of distinct variable conditions. (Contributed by Glauco Siliprandi, 5-Apr-2020.)
|- F/_ k B   &    |- ( k = M -> A = B )   =>    |- ( ( M e. V /\ B e. CC ) -> sum_ k e. { M } A = B )
Theorem	fsumsplitsn 11420*	Separate out a term in a finite sum. (Contributed by Glauco Siliprandi, 5-Apr-2020.)
|- F/ k ph   &    |- F/_ k D   &    |- ( ph -> A e. Fin )   &    |- ( ph -> B e. V )   &    |- ( ph -> -. B e. A )   &    |- ( ( ph /\ k e. A ) -> C e. CC )   &    |- ( k = B -> C = D )   &    |- ( ph -> D e. CC )   =>    |- ( ph -> sum_ k e. ( A u. { B } ) C = ( sum_ k e. A C + D ) )
Theorem	sumsn 11421*	A sum of a singleton is the term. (Contributed by Mario Carneiro, 22-Apr-2014.)
|- ( k = M -> A = B )   =>    |- ( ( M e. V /\ B e. CC ) -> sum_ k e. { M } A = B )
Theorem	fsum1 11422*	The finite sum of A ( k ) from k = M to M (i.e. a sum with only one term) is B i.e. A ( M ). (Contributed by NM, 8-Nov-2005.) (Revised by Mario Carneiro, 21-Apr-2014.)
|- ( k = M -> A = B )   =>    |- ( ( M e. ZZ /\ B e. CC ) -> sum_ k e. ( M ... M ) A = B )
Theorem	sumpr 11423*	A sum over a pair is the sum of the elements. (Contributed by Thierry Arnoux, 12-Dec-2016.)
|- ( k = A -> C = D )   &    |- ( k = B -> C = E )   &    |- ( ph -> ( D e. CC /\ E e. CC ) )   &    |- ( ph -> ( A e. V /\ B e. W ) )   &    |- ( ph -> A =/= B )   =>    |- ( ph -> sum_ k e. { A , B } C = ( D + E ) )
Theorem	sumtp 11424*	A sum over a triple is the sum of the elements. (Contributed by AV, 24-Jul-2020.)
|- ( k = A -> D = E )   &    |- ( k = B -> D = F )   &    |- ( k = C -> D = G )   &    |- ( ph -> ( E e. CC /\ F e. CC /\ G e. CC ) )   &    |- ( ph -> ( A e. V /\ B e. W /\ C e. X ) )   &    |- ( ph -> A =/= B )   &    |- ( ph -> A =/= C )   &    |- ( ph -> B =/= C )   =>    |- ( ph -> sum_ k e. { A , B , C } D = ( ( E + F ) + G ) )
Theorem	sumsns 11425*	A sum of a singleton is the term. (Contributed by Mario Carneiro, 22-Apr-2014.)
|- ( ( M e. V /\ [_ M / k ]_ A e. CC ) -> sum_ k e. { M } A = [_ M / k ]_ A )
Theorem	fsumm1 11426*	Separate out the last term in a finite sum. (Contributed by Mario Carneiro, 26-Apr-2014.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> A e. CC )   &    |- ( k = N -> A = B )   =>    |- ( ph -> sum_ k e. ( M ... N ) A = ( sum_ k e. ( M ... ( N - 1 ) ) A + B ) )
Theorem	fzosump1 11427*	Separate out the last term in a finite sum. (Contributed by Mario Carneiro, 13-Apr-2016.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> A e. CC )   &    |- ( k = N -> A = B )   =>    |- ( ph -> sum_ k e. ( M..^ ( N + 1 ) ) A = ( sum_ k e. ( M..^ N ) A + B ) )
Theorem	fsum1p 11428*	Separate out the first term in a finite sum. (Contributed by NM, 3-Jan-2006.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> A e. CC )   &    |- ( k = M -> A = B )   =>    |- ( ph -> sum_ k e. ( M ... N ) A = ( B + sum_ k e. ( ( M + 1 ) ... N ) A ) )
Theorem	fsumsplitsnun 11429*	Separate out a term in a finite sum by splitting the sum into two parts. (Contributed by Alexander van der Vekens, 1-Sep-2018.) (Revised by AV, 17-Dec-2021.)
|- ( ( A e. Fin /\ ( Z e. V /\ Z e/ A ) /\ A. k e. ( A u. { Z } ) B e. ZZ ) -> sum_ k e. ( A u. { Z } ) B = ( sum_ k e. A B + [_ Z / k ]_ B ) )
Theorem	fsump1 11430*	The addition of the next term in a finite sum of A ( k ) is the current term plus B i.e. A ( N + 1 ). (Contributed by NM, 4-Nov-2005.) (Revised by Mario Carneiro, 21-Apr-2014.)
|- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... ( N + 1 ) ) ) -> A e. CC )   &    |- ( k = ( N + 1 ) -> A = B )   =>    |- ( ph -> sum_ k e. ( M ... ( N + 1 ) ) A = ( sum_ k e. ( M ... N ) A + B ) )
Theorem	isumclim 11431*	An infinite sum equals the value its series converges to. (Contributed by NM, 25-Dec-2005.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ph -> seq M ( + , F ) ~~> B )   =>    |- ( ph -> sum_ k e. Z A = B )
Theorem	isumclim2 11432*	A converging series converges to its infinite sum. (Contributed by NM, 2-Jan-2006.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   =>    |- ( ph -> seq M ( + , F ) ~~> sum_ k e. Z A )
Theorem	isumclim3 11433*	The sequence of partial finite sums of a converging infinite series converges to the infinite sum of the series. Note that j must not occur in A. (Contributed by NM, 9-Jan-2006.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ph -> F e. dom ~~> )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ( ph /\ j e. Z ) -> ( F ` j ) = sum_ k e. ( M ... j ) A )   =>    |- ( ph -> F ~~> sum_ k e. Z A )
Theorem	sumnul 11434*	The sum of a non-convergent infinite series evaluates to the empty set. (Contributed by Paul Chapman, 4-Nov-2007.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ph -> -. seq M ( + , F ) e. dom ~~> )   =>    |- ( ph -> sum_ k e. Z A = (/) )
Theorem	isumcl 11435*	The sum of a converging infinite series is a complex number. (Contributed by NM, 13-Dec-2005.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   =>    |- ( ph -> sum_ k e. Z A e. CC )
Theorem	isummulc2 11436*	An infinite sum multiplied by a constant. (Contributed by NM, 12-Nov-2005.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   &    |- ( ph -> B e. CC )   =>    |- ( ph -> ( B x. sum_ k e. Z A ) = sum_ k e. Z ( B x. A ) )
Theorem	isummulc1 11437*	An infinite sum multiplied by a constant. (Contributed by NM, 13-Nov-2005.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   &    |- ( ph -> B e. CC )   =>    |- ( ph -> ( sum_ k e. Z A x. B ) = sum_ k e. Z ( A x. B ) )
Theorem	isumdivapc 11438*	An infinite sum divided by a constant. (Contributed by NM, 2-Jan-2006.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   &    |- ( ph -> B e. CC )   &    |- ( ph -> B # 0 )   =>    |- ( ph -> ( sum_ k e. Z A / B ) = sum_ k e. Z ( A / B ) )
Theorem	isumrecl 11439*	The sum of a converging infinite real series is a real number. (Contributed by Mario Carneiro, 24-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. RR )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   =>    |- ( ph -> sum_ k e. Z A e. RR )
Theorem	isumge0 11440*	An infinite sum of nonnegative terms is nonnegative. (Contributed by Mario Carneiro, 28-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. RR )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   &    |- ( ( ph /\ k e. Z ) -> 0 <_ A )   =>    |- ( ph -> 0 <_ sum_ k e. Z A )
Theorem	isumadd 11441*	Addition of infinite sums. (Contributed by Mario Carneiro, 18-Aug-2013.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = A )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ( ph /\ k e. Z ) -> ( G ` k ) = B )   &    |- ( ( ph /\ k e. Z ) -> B e. CC )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   &    |- ( ph -> seq M ( + , G ) e. dom ~~> )   =>    |- ( ph -> sum_ k e. Z ( A + B ) = ( sum_ k e. Z A + sum_ k e. Z B ) )
Theorem	sumsplitdc 11442*	Split a sum into two parts. (Contributed by Mario Carneiro, 18-Aug-2013.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> M e. ZZ )   &    |- ( ph -> ( A i^i B ) = (/) )   &    |- ( ph -> ( A u. B ) C_ Z )   &    |- ( ( ph /\ k e. Z ) -> DECID k e. A )   &    |- ( ( ph /\ k e. Z ) -> DECID k e. B )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) = if ( k e. A , C , 0 ) )   &    |- ( ( ph /\ k e. Z ) -> ( G ` k ) = if ( k e. B , C , 0 ) )   &    |- ( ( ph /\ k e. ( A u. B ) ) -> C e. CC )   &    |- ( ph -> seq M ( + , F ) e. dom ~~> )   &    |- ( ph -> seq M ( + , G ) e. dom ~~> )   =>    |- ( ph -> sum_ k e. ( A u. B ) C = ( sum_ k e. A C + sum_ k e. B C ) )
Theorem	fsump1i 11443*	Optimized version of fsump1 11430 for making sums of a concrete number of terms. (Contributed by Mario Carneiro, 23-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- N = ( K + 1 )   &    |- ( k = N -> A = B )   &    |- ( ( ph /\ k e. Z ) -> A e. CC )   &    |- ( ph -> ( K e. Z /\ sum_ k e. ( M ... K ) A = S ) )   &    |- ( ph -> ( S + B ) = T )   =>    |- ( ph -> ( N e. Z /\ sum_ k e. ( M ... N ) A = T ) )
Theorem	fsum2dlemstep 11444*	Lemma for fsum2d 11445- induction step. (Contributed by Mario Carneiro, 23-Apr-2014.) (Revised by Jim Kingdon, 8-Oct-2022.)
|- ( z = <. j , k >. -> D = C )   &    |- ( ph -> A e. Fin )   &    |- ( ( ph /\ j e. A ) -> B e. Fin )   &    |- ( ( ph /\ ( j e. A /\ k e. B ) ) -> C e. CC )   &    |- ( ph -> -. y e. x )   &    |- ( ph -> ( x u. { y } ) C_ A )   &    |- ( ph -> x e. Fin )   &    |- ( ps <-> sum_ j e. x sum_ k e. B C = sum_ z e. U_ j e. x ( { j } X. B ) D )   =>    |- ( ( ph /\ ps ) -> sum_ j e. ( x u. { y } ) sum_ k e. B C = sum_ z e. U_ j e. ( x u. { y } ) ( { j } X. B ) D )
Theorem	fsum2d 11445*	Write a double sum as a sum over a two-dimensional region. Note that B ( j ) is a function of j. (Contributed by Mario Carneiro, 27-Apr-2014.)
|- ( z = <. j , k >. -> D = C )   &    |- ( ph -> A e. Fin )   &    |- ( ( ph /\ j e. A ) -> B e. Fin )   &    |- ( ( ph /\ ( j e. A /\ k e. B ) ) -> C e. CC )   =>    |- ( ph -> sum_ j e. A sum_ k e. B C = sum_ z e. U_ j e. A ( { j } X. B ) D )
Theorem	fsumxp 11446*	Combine two sums into a single sum over the cartesian product. (Contributed by Mario Carneiro, 23-Apr-2014.)
|- ( z = <. j , k >. -> D = C )   &    |- ( ph -> A e. Fin )   &    |- ( ph -> B e. Fin )   &    |- ( ( ph /\ ( j e. A /\ k e. B ) ) -> C e. CC )   =>    |- ( ph -> sum_ j e. A sum_ k e. B C = sum_ z e. ( A X. B ) D )
Theorem	fsumcnv 11447*	Transform a region of summation by using the converse operation. (Contributed by Mario Carneiro, 23-Apr-2014.)
|- ( x = <. j , k >. -> B = D )   &    |- ( y = <. k , j >. -> C = D )   &    |- ( ph -> A e. Fin )   &    |- ( ph -> Rel A )   &    |- ( ( ph /\ x e. A ) -> B e. CC )   =>    |- ( ph -> sum_ x e. A B = sum_ y e. `' A C )
Theorem	fisumcom2 11448*	Interchange order of summation. Note that B ( j ) and D ( k ) are not necessarily constant expressions. (Contributed by Mario Carneiro, 28-Apr-2014.) (Revised by Mario Carneiro, 8-Apr-2016.) (Proof shortened by JJ, 2-Aug-2021.)
|- ( ph -> A e. Fin )   &    |- ( ph -> C e. Fin )   &    |- ( ( ph /\ j e. A ) -> B e. Fin )   &    |- ( ( ph /\ k e. C ) -> D e. Fin )   &    |- ( ph -> ( ( j e. A /\ k e. B ) <-> ( k e. C /\ j e. D ) ) )   &    |- ( ( ph /\ ( j e. A /\ k e. B ) ) -> E e. CC )   =>    |- ( ph -> sum_ j e. A sum_ k e. B E = sum_ k e. C sum_ j e. D E )
Theorem	fsumcom 11449*	Interchange order of summation. (Contributed by NM, 15-Nov-2005.) (Revised by Mario Carneiro, 23-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ph -> B e. Fin )   &    |- ( ( ph /\ ( j e. A /\ k e. B ) ) -> C e. CC )   =>    |- ( ph -> sum_ j e. A sum_ k e. B C = sum_ k e. B sum_ j e. A C )
Theorem	fsum0diaglem 11450*	Lemma for fisum0diag 11451. (Contributed by Mario Carneiro, 28-Apr-2014.) (Revised by Mario Carneiro, 8-Apr-2016.)
|- ( ( j e. ( 0 ... N ) /\ k e. ( 0 ... ( N - j ) ) ) -> ( k e. ( 0 ... N ) /\ j e. ( 0 ... ( N - k ) ) ) )
Theorem	fisum0diag 11451*	Two ways to express "the sum of A ( j , k ) over the triangular region M <_ j, M <_ k, j + k <_ N". (Contributed by NM, 31-Dec-2005.) (Proof shortened by Mario Carneiro, 28-Apr-2014.) (Revised by Mario Carneiro, 8-Apr-2016.)
|- ( ( ph /\ ( j e. ( 0 ... N ) /\ k e. ( 0 ... ( N - j ) ) ) ) -> A e. CC )   &    |- ( ph -> N e. ZZ )   =>    |- ( ph -> sum_ j e. ( 0 ... N ) sum_ k e. ( 0 ... ( N - j ) ) A = sum_ k e. ( 0 ... N ) sum_ j e. ( 0 ... ( N - k ) ) A )
Theorem	mptfzshft 11452*	1-1 onto function in maps-to notation which shifts a finite set of sequential integers. (Contributed by AV, 24-Aug-2019.)
|- ( ph -> K e. ZZ )   &    |- ( ph -> M e. ZZ )   &    |- ( ph -> N e. ZZ )   =>    |- ( ph -> ( j e. ( ( M + K ) ... ( N + K ) ) |-> ( j - K ) ) : ( ( M + K ) ... ( N + K ) ) -1-1-onto-> ( M ... N ) )
Theorem	fsumrev 11453*	Reversal of a finite sum. (Contributed by NM, 26-Nov-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> K e. ZZ )   &    |- ( ph -> M e. ZZ )   &    |- ( ph -> N e. ZZ )   &    |- ( ( ph /\ j e. ( M ... N ) ) -> A e. CC )   &    |- ( j = ( K - k ) -> A = B )   =>    |- ( ph -> sum_ j e. ( M ... N ) A = sum_ k e. ( ( K - N ) ... ( K - M ) ) B )
Theorem	fsumshft 11454*	Index shift of a finite sum. (Contributed by NM, 27-Nov-2005.) (Revised by Mario Carneiro, 24-Apr-2014.) (Proof shortened by AV, 8-Sep-2019.)
|- ( ph -> K e. ZZ )   &    |- ( ph -> M e. ZZ )   &    |- ( ph -> N e. ZZ )   &    |- ( ( ph /\ j e. ( M ... N ) ) -> A e. CC )   &    |- ( j = ( k - K ) -> A = B )   =>    |- ( ph -> sum_ j e. ( M ... N ) A = sum_ k e. ( ( M + K ) ... ( N + K ) ) B )
Theorem	fsumshftm 11455*	Negative index shift of a finite sum. (Contributed by NM, 28-Nov-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> K e. ZZ )   &    |- ( ph -> M e. ZZ )   &    |- ( ph -> N e. ZZ )   &    |- ( ( ph /\ j e. ( M ... N ) ) -> A e. CC )   &    |- ( j = ( k + K ) -> A = B )   =>    |- ( ph -> sum_ j e. ( M ... N ) A = sum_ k e. ( ( M - K ) ... ( N - K ) ) B )
Theorem	fisumrev2 11456*	Reversal of a finite sum. (Contributed by NM, 27-Nov-2005.) (Revised by Mario Carneiro, 13-Apr-2016.)
|- ( ph -> M e. ZZ )   &    |- ( ph -> N e. ZZ )   &    |- ( ( ph /\ j e. ( M ... N ) ) -> A e. CC )   &    |- ( j = ( ( M + N ) - k ) -> A = B )   =>    |- ( ph -> sum_ j e. ( M ... N ) A = sum_ k e. ( M ... N ) B )
Theorem	fisum0diag2 11457*	Two ways to express "the sum of A ( j , k ) over the triangular region 0 <_ j, 0 <_ k, j + k <_ N". (Contributed by Mario Carneiro, 21-Jul-2014.)
|- ( x = k -> B = A )   &    |- ( x = ( k - j ) -> B = C )   &    |- ( ( ph /\ ( j e. ( 0 ... N ) /\ k e. ( 0 ... ( N - j ) ) ) ) -> A e. CC )   &    |- ( ph -> N e. ZZ )   =>    |- ( ph -> sum_ j e. ( 0 ... N ) sum_ k e. ( 0 ... ( N - j ) ) A = sum_ k e. ( 0 ... N ) sum_ j e. ( 0 ... k ) C )
Theorem	fsummulc2 11458*	A finite sum multiplied by a constant. (Contributed by NM, 12-Nov-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ph -> C e. CC )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> ( C x. sum_ k e. A B ) = sum_ k e. A ( C x. B ) )
Theorem	fsummulc1 11459*	A finite sum multiplied by a constant. (Contributed by NM, 13-Nov-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ph -> C e. CC )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> ( sum_ k e. A B x. C ) = sum_ k e. A ( B x. C ) )
Theorem	fsumdivapc 11460*	A finite sum divided by a constant. (Contributed by NM, 2-Jan-2006.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ph -> C e. CC )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   &    |- ( ph -> C # 0 )   =>    |- ( ph -> ( sum_ k e. A B / C ) = sum_ k e. A ( B / C ) )
Theorem	fsumneg 11461*	Negation of a finite sum. (Contributed by Scott Fenton, 12-Jun-2013.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> sum_ k e. A -u B = -u sum_ k e. A B )
Theorem	fsumsub 11462*	Split a finite sum over a subtraction. (Contributed by Scott Fenton, 12-Jun-2013.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   &    |- ( ( ph /\ k e. A ) -> C e. CC )   =>    |- ( ph -> sum_ k e. A ( B - C ) = ( sum_ k e. A B - sum_ k e. A C ) )
Theorem	fsum2mul 11463*	Separate the nested sum of the product C ( j ) x. D ( k ). (Contributed by NM, 13-Nov-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ph -> B e. Fin )   &    |- ( ( ph /\ j e. A ) -> C e. CC )   &    |- ( ( ph /\ k e. B ) -> D e. CC )   =>    |- ( ph -> sum_ j e. A sum_ k e. B ( C x. D ) = ( sum_ j e. A C x. sum_ k e. B D ) )
Theorem	fsumconst 11464*	The sum of constant terms ( k is not free in B). (Contributed by NM, 24-Dec-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ( A e. Fin /\ B e. CC ) -> sum_ k e. A B = ( (♯ ` A ) x. B ) )
Theorem	fsumdifsnconst 11465*	The sum of constant terms ( k is not free in C) over an index set excluding a singleton. (Contributed by AV, 7-Jan-2022.)
|- ( ( A e. Fin /\ B e. A /\ C e. CC ) -> sum_ k e. ( A \ { B } ) C = ( ( (♯ ` A ) - 1 ) x. C ) )
Theorem	modfsummodlem1 11466*	Lemma for modfsummod 11468. (Contributed by Alexander van der Vekens, 1-Sep-2018.)
|- ( A. k e. ( A u. { z } ) B e. ZZ -> [_ z / k ]_ B e. ZZ )
Theorem	modfsummodlemstep 11467*	Induction step for modfsummod 11468. (Contributed by Alexander van der Vekens, 1-Sep-2018.) (Revised by Jim Kingdon, 12-Oct-2022.)
|- ( ph -> A e. Fin )   &    |- ( ph -> N e. NN )   &    |- ( ph -> A. k e. ( A u. { z } ) B e. ZZ )   &    |- ( ph -> -. z e. A )   &    |- ( ph -> ( sum_ k e. A B mod N ) = ( sum_ k e. A ( B mod N ) mod N ) )   =>    |- ( ph -> ( sum_ k e. ( A u. { z } ) B mod N ) = ( sum_ k e. ( A u. { z } ) ( B mod N ) mod N ) )
Theorem	modfsummod 11468*	A finite sum modulo a positive integer equals the finite sum of their summands modulo the positive integer, modulo the positive integer. (Contributed by Alexander van der Vekens, 1-Sep-2018.)
|- ( ph -> N e. NN )   &    |- ( ph -> A e. Fin )   &    |- ( ph -> A. k e. A B e. ZZ )   =>    |- ( ph -> ( sum_ k e. A B mod N ) = ( sum_ k e. A ( B mod N ) mod N ) )
Theorem	fsumge0 11469*	If all of the terms of a finite sum are nonnegative, so is the sum. (Contributed by NM, 26-Dec-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. RR )   &    |- ( ( ph /\ k e. A ) -> 0 <_ B )   =>    |- ( ph -> 0 <_ sum_ k e. A B )
Theorem	fsumlessfi 11470*	A shorter sum of nonnegative terms is no greater than a longer one. (Contributed by NM, 26-Dec-2005.) (Revised by Jim Kingdon, 12-Oct-2022.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. RR )   &    |- ( ( ph /\ k e. A ) -> 0 <_ B )   &    |- ( ph -> C C_ A )   &    |- ( ph -> C e. Fin )   =>    |- ( ph -> sum_ k e. C B <_ sum_ k e. A B )
Theorem	fsumge1 11471*	A sum of nonnegative numbers is greater than or equal to any one of its terms. (Contributed by Jeff Madsen, 2-Sep-2009.) (Proof shortened by Mario Carneiro, 4-Jun-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. RR )   &    |- ( ( ph /\ k e. A ) -> 0 <_ B )   &    |- ( k = M -> B = C )   &    |- ( ph -> M e. A )   =>    |- ( ph -> C <_ sum_ k e. A B )
Theorem	fsum00 11472*	A sum of nonnegative numbers is zero iff all terms are zero. (Contributed by Jeff Madsen, 2-Sep-2009.) (Proof shortened by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. RR )   &    |- ( ( ph /\ k e. A ) -> 0 <_ B )   =>    |- ( ph -> ( sum_ k e. A B = 0 <-> A. k e. A B = 0 ) )
Theorem	fsumle 11473*	If all of the terms of finite sums compare, so do the sums. (Contributed by NM, 11-Dec-2005.) (Proof shortened by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. RR )   &    |- ( ( ph /\ k e. A ) -> C e. RR )   &    |- ( ( ph /\ k e. A ) -> B <_ C )   =>    |- ( ph -> sum_ k e. A B <_ sum_ k e. A C )
Theorem	fsumlt 11474*	If every term in one finite sum is less than the corresponding term in another, then the first sum is less than the second. (Contributed by Jeff Madsen, 2-Sep-2009.) (Revised by Mario Carneiro, 3-Jun-2014.)
|- ( ph -> A e. Fin )   &    |- ( ph -> A =/= (/) )   &    |- ( ( ph /\ k e. A ) -> B e. RR )   &    |- ( ( ph /\ k e. A ) -> C e. RR )   &    |- ( ( ph /\ k e. A ) -> B < C )   =>    |- ( ph -> sum_ k e. A B < sum_ k e. A C )
Theorem	fsumabs 11475*	Generalized triangle inequality: the absolute value of a finite sum is less than or equal to the sum of absolute values. (Contributed by NM, 9-Nov-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> ( abs ` sum_ k e. A B ) <_ sum_ k e. A ( abs ` B ) )
Theorem	telfsumo 11476*	Sum of a telescoping series, using half-open intervals. (Contributed by Mario Carneiro, 2-May-2016.)
|- ( k = j -> A = B )   &    |- ( k = ( j + 1 ) -> A = C )   &    |- ( k = M -> A = D )   &    |- ( k = N -> A = E )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> A e. CC )   =>    |- ( ph -> sum_ j e. ( M..^ N ) ( B - C ) = ( D - E ) )
Theorem	telfsumo2 11477*	Sum of a telescoping series. (Contributed by Mario Carneiro, 2-May-2016.)
|- ( k = j -> A = B )   &    |- ( k = ( j + 1 ) -> A = C )   &    |- ( k = M -> A = D )   &    |- ( k = N -> A = E )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> A e. CC )   =>    |- ( ph -> sum_ j e. ( M..^ N ) ( C - B ) = ( E - D ) )
Theorem	telfsum 11478*	Sum of a telescoping series. (Contributed by Scott Fenton, 24-Apr-2014.) (Revised by Mario Carneiro, 2-May-2016.)
|- ( k = j -> A = B )   &    |- ( k = ( j + 1 ) -> A = C )   &    |- ( k = M -> A = D )   &    |- ( k = ( N + 1 ) -> A = E )   &    |- ( ph -> N e. ZZ )   &    |- ( ph -> ( N + 1 ) e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... ( N + 1 ) ) ) -> A e. CC )   =>    |- ( ph -> sum_ j e. ( M ... N ) ( B - C ) = ( D - E ) )
Theorem	telfsum2 11479*	Sum of a telescoping series. (Contributed by Mario Carneiro, 15-Jun-2014.) (Revised by Mario Carneiro, 2-May-2016.)
|- ( k = j -> A = B )   &    |- ( k = ( j + 1 ) -> A = C )   &    |- ( k = M -> A = D )   &    |- ( k = ( N + 1 ) -> A = E )   &    |- ( ph -> N e. ZZ )   &    |- ( ph -> ( N + 1 ) e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... ( N + 1 ) ) ) -> A e. CC )   =>    |- ( ph -> sum_ j e. ( M ... N ) ( C - B ) = ( E - D ) )
Theorem	fsumparts 11480*	Summation by parts. (Contributed by Mario Carneiro, 13-Apr-2016.)
|- ( k = j -> ( A = B /\ V = W ) )   &    |- ( k = ( j + 1 ) -> ( A = C /\ V = X ) )   &    |- ( k = M -> ( A = D /\ V = Y ) )   &    |- ( k = N -> ( A = E /\ V = Z ) )   &    |- ( ph -> N e. ( ZZ>= ` M ) )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> A e. CC )   &    |- ( ( ph /\ k e. ( M ... N ) ) -> V e. CC )   =>    |- ( ph -> sum_ j e. ( M..^ N ) ( B x. ( X - W ) ) = ( ( ( E x. Z ) - ( D x. Y ) ) - sum_ j e. ( M..^ N ) ( ( C - B ) x. X ) ) )
Theorem	fsumrelem 11481*	Lemma for fsumre 11482, fsumim 11483, and fsumcj 11484. (Contributed by Mario Carneiro, 25-Jul-2014.) (Revised by Mario Carneiro, 27-Dec-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   &    |- F : CC --> CC   &    |- ( ( x e. CC /\ y e. CC ) -> ( F ` ( x + y ) ) = ( ( F ` x ) + ( F ` y ) ) )   =>    |- ( ph -> ( F ` sum_ k e. A B ) = sum_ k e. A ( F ` B ) )
Theorem	fsumre 11482*	The real part of a sum. (Contributed by Paul Chapman, 9-Nov-2007.) (Revised by Mario Carneiro, 25-Jul-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> ( Re ` sum_ k e. A B ) = sum_ k e. A ( Re ` B ) )
Theorem	fsumim 11483*	The imaginary part of a sum. (Contributed by Paul Chapman, 9-Nov-2007.) (Revised by Mario Carneiro, 25-Jul-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> ( Im ` sum_ k e. A B ) = sum_ k e. A ( Im ` B ) )
Theorem	fsumcj 11484*	The complex conjugate of a sum. (Contributed by Paul Chapman, 9-Nov-2007.) (Revised by Mario Carneiro, 25-Jul-2014.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ k e. A ) -> B e. CC )   =>    |- ( ph -> ( * ` sum_ k e. A B ) = sum_ k e. A ( * ` B ) )
Theorem	iserabs 11485*	Generalized triangle inequality: the absolute value of an infinite sum is less than or equal to the sum of absolute values. (Contributed by Paul Chapman, 10-Sep-2007.) (Revised by Jim Kingdon, 14-Dec-2022.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> seq M ( + , F ) ~~> A )   &    |- ( ph -> seq M ( + , G ) ~~> B )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) e. CC )   &    |- ( ( ph /\ k e. Z ) -> ( G ` k ) = ( abs ` ( F ` k ) ) )   =>    |- ( ph -> ( abs ` A ) <_ B )
Theorem	cvgcmpub 11486*	An upper bound for the limit of a real infinite series. This theorem can also be used to compare two infinite series. (Contributed by Mario Carneiro, 24-Mar-2014.)
|- Z = ( ZZ>= ` M )   &    |- ( ph -> N e. Z )   &    |- ( ( ph /\ k e. Z ) -> ( F ` k ) e. RR )   &    |- ( ( ph /\ k e. Z ) -> ( G ` k ) e. RR )   &    |- ( ph -> seq M ( + , F ) ~~> A )   &    |- ( ph -> seq M ( + , G ) ~~> B )   &    |- ( ( ph /\ k e. Z ) -> ( G ` k ) <_ ( F ` k ) )   =>    |- ( ph -> B <_ A )
Theorem	fsumiun 11487*	Sum over a disjoint indexed union. (Contributed by Mario Carneiro, 1-Jul-2015.) (Revised by Mario Carneiro, 10-Dec-2016.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ x e. A ) -> B e. Fin )   &    |- ( ph -> Disj x e. A B )   &    |- ( ( ph /\ ( x e. A /\ k e. B ) ) -> C e. CC )   =>    |- ( ph -> sum_ k e. U_ x e. A B C = sum_ x e. A sum_ k e. B C )
Theorem	hashiun 11488*	The cardinality of a disjoint indexed union. (Contributed by Mario Carneiro, 24-Jan-2015.) (Revised by Mario Carneiro, 10-Dec-2016.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ x e. A ) -> B e. Fin )   &    |- ( ph -> Disj x e. A B )   =>    |- ( ph -> (♯ ` U_ x e. A B ) = sum_ x e. A (♯ ` B ) )
Theorem	hash2iun 11489*	The cardinality of a nested disjoint indexed union. (Contributed by AV, 9-Jan-2022.)
|- ( ph -> A e. Fin )   &    |- ( ( ph /\ x e. A ) -> B e. Fin )   &    |- ( ( ph /\ x e. A /\ y e. B ) -> C e. Fin )   &    |- ( ph -> Disj x e. A U_ y e. B C )   &    |- ( ( ph /\ x e. A ) -> Disj y e. B C )   =>    |- ( ph -> (♯ ` U_ x e. A U_ y e. B C ) = sum_ x e. A sum_ y e. B (♯ ` C ) )
Theorem	hash2iun1dif1 11490*	The cardinality of a nested disjoint indexed union. (Contributed by AV, 9-Jan-2022.)
|- ( ph -> A e. Fin )   &    |- B = ( A \ { x } )   &    |- ( ( ph /\ x e. A /\ y e. B ) -> C e. Fin )   &    |- ( ph -> Disj x e. A U_ y e. B C )   &    |- ( ( ph /\ x e. A ) -> Disj y e. B C )   &    |- ( ( ph /\ x e. A /\ y e. B ) -> (♯ ` C ) = 1 )   =>    |- ( ph -> (♯ ` U_ x e. A U_ y e. B C ) = ( (♯ ` A ) x. ( (♯ ` A ) - 1 ) ) )
Theorem	hashrabrex 11491*	The number of elements in a class abstraction with a restricted existential quantification. (Contributed by Alexander van der Vekens, 29-Jul-2018.)
|- ( ph -> Y e. Fin )   &    |- ( ( ph /\ y e. Y ) -> { x e. X | ps } e. Fin )   &    |- ( ph -> Disj y e. Y { x e. X | ps } )   =>    |- ( ph -> (♯ ` { x e. X | E. y e. Y ps } ) = sum_ y e. Y (♯ ` { x e. X | ps } ) )
Theorem	hashuni 11492*	The cardinality of a disjoint union. (Contributed by Mario Carneiro, 24-Jan-2015.)
|- ( ph -> A e. Fin )   &    |- ( ph -> A C_ Fin )   &    |- ( ph -> Disj x e. A x )   =>    |- ( ph -> (♯ ` U. A ) = sum_ x e. A (♯ ` x ) )
4.8.3  The binomial theorem
Theorem	binomlem 11493*	Lemma for binom 11494 (binomial theorem). Inductive step. (Contributed by NM, 6-Dec-2005.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ph -> A e. CC )   &    |- ( ph -> B e. CC )   &    |- ( ph -> N e. NN0 )   &    |- ( ps -> ( ( A + B ) ^ N ) = sum_ k e. ( 0 ... N ) ( ( N _C k ) x. ( ( A ^ ( N - k ) ) x. ( B ^ k ) ) ) )   =>    |- ( ( ph /\ ps ) -> ( ( A + B ) ^ ( N + 1 ) ) = sum_ k e. ( 0 ... ( N + 1 ) ) ( ( ( N + 1 ) _C k ) x. ( ( A ^ ( ( N + 1 ) - k ) ) x. ( B ^ k ) ) ) )
Theorem	binom 11494*	The binomial theorem: ( A + B ) ^ N is the sum from k = 0 to N of ( N _C k ) x. ( ( A ^ k ) x. ( B ^ ( N - k ) ). Theorem 15-2.8 of [Gleason] p. 296. This part of the proof sets up the induction and does the base case, with the bulk of the work (the induction step) in binomlem 11493. This is Metamath 100 proof #44. (Contributed by NM, 7-Dec-2005.) (Proof shortened by Mario Carneiro, 24-Apr-2014.)
|- ( ( A e. CC /\ B e. CC /\ N e. NN0 ) -> ( ( A + B ) ^ N ) = sum_ k e. ( 0 ... N ) ( ( N _C k ) x. ( ( A ^ ( N - k ) ) x. ( B ^ k ) ) ) )
Theorem	binom1p 11495*	Special case of the binomial theorem for ( 1 + A ) ^ N. (Contributed by Paul Chapman, 10-May-2007.)
|- ( ( A e. CC /\ N e. NN0 ) -> ( ( 1 + A ) ^ N ) = sum_ k e. ( 0 ... N ) ( ( N _C k ) x. ( A ^ k ) ) )
Theorem	binom11 11496*	Special case of the binomial theorem for 2 ^ N. (Contributed by Mario Carneiro, 13-Mar-2014.)
|- ( N e. NN0 -> ( 2 ^ N ) = sum_ k e. ( 0 ... N ) ( N _C k ) )
Theorem	binom1dif 11497*	A summation for the difference between ( ( A + 1 ) ^ N ) and ( A ^ N ). (Contributed by Scott Fenton, 9-Apr-2014.) (Revised by Mario Carneiro, 22-May-2014.)
|- ( ( A e. CC /\ N e. NN0 ) -> ( ( ( A + 1 ) ^ N ) - ( A ^ N ) ) = sum_ k e. ( 0 ... ( N - 1 ) ) ( ( N _C k ) x. ( A ^ k ) ) )
Theorem	bcxmaslem1 11498	Lemma for bcxmas 11499. (Contributed by Paul Chapman, 18-May-2007.)
|- ( A = B -> ( ( N + A ) _C A ) = ( ( N + B ) _C B ) )
Theorem	bcxmas 11499*	Parallel summation (Christmas Stocking) theorem for Pascal's Triangle. (Contributed by Paul Chapman, 18-May-2007.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- ( ( N e. NN0 /\ M e. NN0 ) -> ( ( ( N + 1 ) + M ) _C M ) = sum_ j e. ( 0 ... M ) ( ( N + j ) _C j ) )
4.8.4  Infinite sums (cont.)
Theorem	isumshft 11500*	Index shift of an infinite sum. (Contributed by Paul Chapman, 31-Oct-2007.) (Revised by Mario Carneiro, 24-Apr-2014.)
|- Z = ( ZZ>= ` M )   &    |- W = ( ZZ>= ` ( M + K ) )   &    |- ( j = ( K + k ) -> A = B )   &    |- ( ph -> K e. ZZ )   &    |- ( ph -> M e. ZZ )   &    |- ( ( ph /\ j e. W ) -> A e. CC )   =>    |- ( ph -> sum_ j e. W A = sum_ k e. Z B )