P. 94 of Theorem List - Intuitionistic Logic Explorer

Theorem List for Intuitionistic Logic Explorer - 9301-9400   *Has distinct variable group(s)

Type	Label	Description
Statement
Theorem	zdivadd 9301	Property of divisibility: if D divides A and B then it divides A + B. (Contributed by NM, 3-Oct-2008.)
|- ( ( ( D e. NN /\ A e. ZZ /\ B e. ZZ ) /\ ( ( A / D ) e. ZZ /\ ( B / D ) e. ZZ ) ) -> ( ( A + B ) / D ) e. ZZ )
Theorem	zdivmul 9302	Property of divisibility: if D divides A then it divides B x. A. (Contributed by NM, 3-Oct-2008.)
|- ( ( ( D e. NN /\ A e. ZZ /\ B e. ZZ ) /\ ( A / D ) e. ZZ ) -> ( ( B x. A ) / D ) e. ZZ )
Theorem	zextle 9303*	An extensionality-like property for integer ordering. (Contributed by NM, 29-Oct-2005.)
|- ( ( M e. ZZ /\ N e. ZZ /\ A. k e. ZZ ( k <_ M <-> k <_ N ) ) -> M = N )
Theorem	zextlt 9304*	An extensionality-like property for integer ordering. (Contributed by NM, 29-Oct-2005.)
|- ( ( M e. ZZ /\ N e. ZZ /\ A. k e. ZZ ( k < M <-> k < N ) ) -> M = N )
Theorem	recnz 9305	The reciprocal of a number greater than 1 is not an integer. (Contributed by NM, 3-May-2005.)
|- ( ( A e. RR /\ 1 < A ) -> -. ( 1 / A ) e. ZZ )
Theorem	btwnnz 9306	A number between an integer and its successor is not an integer. (Contributed by NM, 3-May-2005.)
|- ( ( A e. ZZ /\ A < B /\ B < ( A + 1 ) ) -> -. B e. ZZ )
Theorem	gtndiv 9307	A larger number does not divide a smaller positive integer. (Contributed by NM, 3-May-2005.)
|- ( ( A e. RR /\ B e. NN /\ B < A ) -> -. ( B / A ) e. ZZ )
Theorem	halfnz 9308	One-half is not an integer. (Contributed by NM, 31-Jul-2004.)
|- -. ( 1 / 2 ) e. ZZ
Theorem	3halfnz 9309	Three halves is not an integer. (Contributed by AV, 2-Jun-2020.)
|- -. ( 3 / 2 ) e. ZZ
Theorem	suprzclex 9310*	The supremum of a set of integers is an element of the set. (Contributed by Jim Kingdon, 20-Dec-2021.)
|- ( ph -> E. x e. RR ( A. y e. A -. x < y /\ A. y e. RR ( y < x -> E. z e. A y < z ) ) )   &    |- ( ph -> A C_ ZZ )   =>    |- ( ph -> sup ( A , RR , < ) e. A )
Theorem	prime 9311*	Two ways to express " A is a prime number (or 1)". (Contributed by NM, 4-May-2005.)
|- ( A e. NN -> ( A. x e. NN ( ( A / x ) e. NN -> ( x = 1 \/ x = A ) ) <-> A. x e. NN ( ( 1 < x /\ x <_ A /\ ( A / x ) e. NN ) -> x = A ) ) )
Theorem	msqznn 9312	The square of a nonzero integer is a positive integer. (Contributed by NM, 2-Aug-2004.)
|- ( ( A e. ZZ /\ A =/= 0 ) -> ( A x. A ) e. NN )
Theorem	zneo 9313	No even integer equals an odd integer (i.e. no integer can be both even and odd). Exercise 10(a) of [Apostol] p. 28. (Contributed by NM, 31-Jul-2004.) (Proof shortened by Mario Carneiro, 18-May-2014.)
|- ( ( A e. ZZ /\ B e. ZZ ) -> ( 2 x. A ) =/= ( ( 2 x. B ) + 1 ) )
Theorem	nneoor 9314	A positive integer is even or odd. (Contributed by Jim Kingdon, 15-Mar-2020.)
|- ( N e. NN -> ( ( N / 2 ) e. NN \/ ( ( N + 1 ) / 2 ) e. NN ) )
Theorem	nneo 9315	A positive integer is even or odd but not both. (Contributed by NM, 1-Jan-2006.) (Proof shortened by Mario Carneiro, 18-May-2014.)
|- ( N e. NN -> ( ( N / 2 ) e. NN <-> -. ( ( N + 1 ) / 2 ) e. NN ) )
Theorem	nneoi 9316	A positive integer is even or odd but not both. (Contributed by NM, 20-Aug-2001.)
|- N e. NN   =>    |- ( ( N / 2 ) e. NN <-> -. ( ( N + 1 ) / 2 ) e. NN )
Theorem	zeo 9317	An integer is even or odd. (Contributed by NM, 1-Jan-2006.)
|- ( N e. ZZ -> ( ( N / 2 ) e. ZZ \/ ( ( N + 1 ) / 2 ) e. ZZ ) )
Theorem	zeo2 9318	An integer is even or odd but not both. (Contributed by Mario Carneiro, 12-Sep-2015.)
|- ( N e. ZZ -> ( ( N / 2 ) e. ZZ <-> -. ( ( N + 1 ) / 2 ) e. ZZ ) )
Theorem	peano2uz2 9319*	Second Peano postulate for upper integers. (Contributed by NM, 3-Oct-2004.)
|- ( ( A e. ZZ /\ B e. { x e. ZZ | A <_ x } ) -> ( B + 1 ) e. { x e. ZZ | A <_ x } )
Theorem	peano5uzti 9320*	Peano's inductive postulate for upper integers. (Contributed by NM, 6-Jul-2005.) (Revised by Mario Carneiro, 25-Jul-2013.)
|- ( N e. ZZ -> ( ( N e. A /\ A. x e. A ( x + 1 ) e. A ) -> { k e. ZZ | N <_ k } C_ A ) )
Theorem	peano5uzi 9321*	Peano's inductive postulate for upper integers. (Contributed by NM, 6-Jul-2005.) (Revised by Mario Carneiro, 3-May-2014.)
|- N e. ZZ   =>    |- ( ( N e. A /\ A. x e. A ( x + 1 ) e. A ) -> { k e. ZZ | N <_ k } C_ A )
Theorem	dfuzi 9322*	An expression for the upper integers that start at N that is analogous to dfnn2 8880 for positive integers. (Contributed by NM, 6-Jul-2005.) (Proof shortened by Mario Carneiro, 3-May-2014.)
|- N e. ZZ   =>    |- { z e. ZZ | N <_ z } = |^| { x | ( N e. x /\ A. y e. x ( y + 1 ) e. x ) }
Theorem	uzind 9323*	Induction on the upper integers that start at M. The first four hypotheses give us the substitution instances we need; the last two are the basis and the induction step. (Contributed by NM, 5-Jul-2005.)
|- ( j = M -> ( ph <-> ps ) )   &    |- ( j = k -> ( ph <-> ch ) )   &    |- ( j = ( k + 1 ) -> ( ph <-> th ) )   &    |- ( j = N -> ( ph <-> ta ) )   &    |- ( M e. ZZ -> ps )   &    |- ( ( M e. ZZ /\ k e. ZZ /\ M <_ k ) -> ( ch -> th ) )   =>    |- ( ( M e. ZZ /\ N e. ZZ /\ M <_ N ) -> ta )
Theorem	uzind2 9324*	Induction on the upper integers that start after an integer M. The first four hypotheses give us the substitution instances we need; the last two are the basis and the induction step. (Contributed by NM, 25-Jul-2005.)
|- ( j = ( M + 1 ) -> ( ph <-> ps ) )   &    |- ( j = k -> ( ph <-> ch ) )   &    |- ( j = ( k + 1 ) -> ( ph <-> th ) )   &    |- ( j = N -> ( ph <-> ta ) )   &    |- ( M e. ZZ -> ps )   &    |- ( ( M e. ZZ /\ k e. ZZ /\ M < k ) -> ( ch -> th ) )   =>    |- ( ( M e. ZZ /\ N e. ZZ /\ M < N ) -> ta )
Theorem	uzind3 9325*	Induction on the upper integers that start at an integer M. The first four hypotheses give us the substitution instances we need, and the last two are the basis and the induction step. (Contributed by NM, 26-Jul-2005.)
|- ( j = M -> ( ph <-> ps ) )   &    |- ( j = m -> ( ph <-> ch ) )   &    |- ( j = ( m + 1 ) -> ( ph <-> th ) )   &    |- ( j = N -> ( ph <-> ta ) )   &    |- ( M e. ZZ -> ps )   &    |- ( ( M e. ZZ /\ m e. { k e. ZZ | M <_ k } ) -> ( ch -> th ) )   =>    |- ( ( M e. ZZ /\ N e. { k e. ZZ | M <_ k } ) -> ta )
Theorem	nn0ind 9326*	Principle of Mathematical Induction (inference schema) on nonnegative integers. The first four hypotheses give us the substitution instances we need; the last two are the basis and the induction step. (Contributed by NM, 13-May-2004.)
|- ( x = 0 -> ( ph <-> ps ) )   &    |- ( x = y -> ( ph <-> ch ) )   &    |- ( x = ( y + 1 ) -> ( ph <-> th ) )   &    |- ( x = A -> ( ph <-> ta ) )   &    |- ps   &    |- ( y e. NN0 -> ( ch -> th ) )   =>    |- ( A e. NN0 -> ta )
Theorem	fzind 9327*	Induction on the integers from M to N inclusive . The first four hypotheses give us the substitution instances we need; the last two are the basis and the induction step. (Contributed by Paul Chapman, 31-Mar-2011.)
|- ( x = M -> ( ph <-> ps ) )   &    |- ( x = y -> ( ph <-> ch ) )   &    |- ( x = ( y + 1 ) -> ( ph <-> th ) )   &    |- ( x = K -> ( ph <-> ta ) )   &    |- ( ( M e. ZZ /\ N e. ZZ /\ M <_ N ) -> ps )   &    |- ( ( ( M e. ZZ /\ N e. ZZ ) /\ ( y e. ZZ /\ M <_ y /\ y < N ) ) -> ( ch -> th ) )   =>    |- ( ( ( M e. ZZ /\ N e. ZZ ) /\ ( K e. ZZ /\ M <_ K /\ K <_ N ) ) -> ta )
Theorem	fnn0ind 9328*	Induction on the integers from 0 to N inclusive . The first four hypotheses give us the substitution instances we need; the last two are the basis and the induction step. (Contributed by Paul Chapman, 31-Mar-2011.)
|- ( x = 0 -> ( ph <-> ps ) )   &    |- ( x = y -> ( ph <-> ch ) )   &    |- ( x = ( y + 1 ) -> ( ph <-> th ) )   &    |- ( x = K -> ( ph <-> ta ) )   &    |- ( N e. NN0 -> ps )   &    |- ( ( N e. NN0 /\ y e. NN0 /\ y < N ) -> ( ch -> th ) )   =>    |- ( ( N e. NN0 /\ K e. NN0 /\ K <_ N ) -> ta )
Theorem	nn0ind-raph 9329*	Principle of Mathematical Induction (inference schema) on nonnegative integers. The first four hypotheses give us the substitution instances we need; the last two are the basis and the induction step. Raph Levien remarks: "This seems a bit painful. I wonder if an explicit substitution version would be easier." (Contributed by Raph Levien, 10-Apr-2004.)
|- ( x = 0 -> ( ph <-> ps ) )   &    |- ( x = y -> ( ph <-> ch ) )   &    |- ( x = ( y + 1 ) -> ( ph <-> th ) )   &    |- ( x = A -> ( ph <-> ta ) )   &    |- ps   &    |- ( y e. NN0 -> ( ch -> th ) )   =>    |- ( A e. NN0 -> ta )
Theorem	zindd 9330*	Principle of Mathematical Induction on all integers, deduction version. The first five hypotheses give the substitutions; the last three are the basis, the induction, and the extension to negative numbers. (Contributed by Paul Chapman, 17-Apr-2009.) (Proof shortened by Mario Carneiro, 4-Jan-2017.)
|- ( x = 0 -> ( ph <-> ps ) )   &    |- ( x = y -> ( ph <-> ch ) )   &    |- ( x = ( y + 1 ) -> ( ph <-> ta ) )   &    |- ( x = -u y -> ( ph <-> th ) )   &    |- ( x = A -> ( ph <-> et ) )   &    |- ( ze -> ps )   &    |- ( ze -> ( y e. NN0 -> ( ch -> ta ) ) )   &    |- ( ze -> ( y e. NN -> ( ch -> th ) ) )   =>    |- ( ze -> ( A e. ZZ -> et ) )
Theorem	btwnz 9331*	Any real number can be sandwiched between two integers. Exercise 2 of [Apostol] p. 28. (Contributed by NM, 10-Nov-2004.)
|- ( A e. RR -> ( E. x e. ZZ x < A /\ E. y e. ZZ A < y ) )
Theorem	nn0zd 9332	A positive integer is an integer. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. NN0 )   =>    |- ( ph -> A e. ZZ )
Theorem	nnzd 9333	A nonnegative integer is an integer. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. NN )   =>    |- ( ph -> A e. ZZ )
Theorem	zred 9334	An integer is a real number. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. ZZ )   =>    |- ( ph -> A e. RR )
Theorem	zcnd 9335	An integer is a complex number. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. ZZ )   =>    |- ( ph -> A e. CC )
Theorem	znegcld 9336	Closure law for negative integers. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. ZZ )   =>    |- ( ph -> -u A e. ZZ )
Theorem	peano2zd 9337	Deduction from second Peano postulate generalized to integers. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. ZZ )   =>    |- ( ph -> ( A + 1 ) e. ZZ )
Theorem	zaddcld 9338	Closure of addition of integers. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. ZZ )   &    |- ( ph -> B e. ZZ )   =>    |- ( ph -> ( A + B ) e. ZZ )
Theorem	zsubcld 9339	Closure of subtraction of integers. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. ZZ )   &    |- ( ph -> B e. ZZ )   =>    |- ( ph -> ( A - B ) e. ZZ )
Theorem	zmulcld 9340	Closure of multiplication of integers. (Contributed by Mario Carneiro, 28-May-2016.)
|- ( ph -> A e. ZZ )   &    |- ( ph -> B e. ZZ )   =>    |- ( ph -> ( A x. B ) e. ZZ )
Theorem	zadd2cl 9341	Increasing an integer by 2 results in an integer. (Contributed by Alexander van der Vekens, 16-Sep-2018.)
|- ( N e. ZZ -> ( N + 2 ) e. ZZ )
Theorem	btwnapz 9342	A number between an integer and its successor is apart from any integer. (Contributed by Jim Kingdon, 6-Jan-2023.)
|- ( ph -> A e. ZZ )   &    |- ( ph -> B e. RR )   &    |- ( ph -> C e. ZZ )   &    |- ( ph -> A < B )   &    |- ( ph -> B < ( A + 1 ) )   =>    |- ( ph -> B # C )
4.4.10  Decimal arithmetic
Syntax	cdc 9343	Constant used for decimal constructor.
class ; A B
Definition	df-dec 9344	Define the "decimal constructor", which is used to build up "decimal integers" or "numeric terms" in base 1 0. For example, (;;; 1 0 0 0 + ;;; 2 0 0 0 ) = ;;; 3 0 0 0 1kp2ke3k 13759. (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 1-Aug-2021.)
|- ; A B = ( ( ( 9 + 1 ) x. A ) + B )
Theorem	9p1e10 9345	9 + 1 = 10. (Contributed by Mario Carneiro, 18-Apr-2015.) (Revised by Stanislas Polu, 7-Apr-2020.) (Revised by AV, 1-Aug-2021.)
|- ( 9 + 1 ) = ; 1 0
Theorem	dfdec10 9346	Version of the definition of the "decimal constructor" using ; 1 0 instead of the symbol 10. Of course, this statement cannot be used as definition, because it uses the "decimal constructor". (Contributed by AV, 1-Aug-2021.)
|- ; A B = ( (; 1 0 x. A ) + B )
Theorem	deceq1 9347	Equality theorem for the decimal constructor. (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- ( A = B -> ; A C = ; B C )
Theorem	deceq2 9348	Equality theorem for the decimal constructor. (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- ( A = B -> ; C A = ; C B )
Theorem	deceq1i 9349	Equality theorem for the decimal constructor. (Contributed by Mario Carneiro, 17-Apr-2015.)
|- A = B   =>    |- ; A C = ; B C
Theorem	deceq2i 9350	Equality theorem for the decimal constructor. (Contributed by Mario Carneiro, 17-Apr-2015.)
|- A = B   =>    |- ; C A = ; C B
Theorem	deceq12i 9351	Equality theorem for the decimal constructor. (Contributed by Mario Carneiro, 17-Apr-2015.)
|- A = B   &    |- C = D   =>    |- ; A C = ; B D
Theorem	numnncl 9352	Closure for a numeral (with units place). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   &    |- B e. NN   =>    |- ( ( T x. A ) + B ) e. NN
Theorem	num0u 9353	Add a zero in the units place. (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   =>    |- ( T x. A ) = ( ( T x. A ) + 0 )
Theorem	num0h 9354	Add a zero in the higher places. (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   =>    |- A = ( ( T x. 0 ) + A )
Theorem	numcl 9355	Closure for a decimal integer (with units place). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   &    |- B e. NN0   =>    |- ( ( T x. A ) + B ) e. NN0
Theorem	numsuc 9356	The successor of a decimal integer (no carry). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   &    |- B e. NN0   &    |- ( B + 1 ) = C   &    |- N = ( ( T x. A ) + B )   =>    |- ( N + 1 ) = ( ( T x. A ) + C )
Theorem	deccl 9357	Closure for a numeral. (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   =>    |- ; A B e. NN0
Theorem	10nn 9358	10 is a positive integer. (Contributed by NM, 8-Nov-2012.) (Revised by AV, 6-Sep-2021.)
|- ; 1 0 e. NN
Theorem	10pos 9359	The number 10 is positive. (Contributed by NM, 5-Feb-2007.) (Revised by AV, 8-Sep-2021.)
|- 0 < ; 1 0
Theorem	10nn0 9360	10 is a nonnegative integer. (Contributed by Mario Carneiro, 19-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- ; 1 0 e. NN0
Theorem	10re 9361	The number 10 is real. (Contributed by NM, 5-Feb-2007.) (Revised by AV, 8-Sep-2021.)
|- ; 1 0 e. RR
Theorem	decnncl 9362	Closure for a numeral. (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN   =>    |- ; A B e. NN
Theorem	dec0u 9363	Add a zero in the units place. (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   =>    |- (; 1 0 x. A ) = ; A 0
Theorem	dec0h 9364	Add a zero in the higher places. (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   =>    |- A = ; 0 A
Theorem	numnncl2 9365	Closure for a decimal integer (zero units place). (Contributed by Mario Carneiro, 9-Mar-2015.)
|- T e. NN   &    |- A e. NN   =>    |- ( ( T x. A ) + 0 ) e. NN
Theorem	decnncl2 9366	Closure for a decimal integer (zero units place). (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- A e. NN   =>    |- ; A 0 e. NN
Theorem	numlt 9367	Comparing two decimal integers (equal higher places). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN   &    |- A e. NN0   &    |- B e. NN0   &    |- C e. NN   &    |- B < C   =>    |- ( ( T x. A ) + B ) < ( ( T x. A ) + C )
Theorem	numltc 9368	Comparing two decimal integers (unequal higher places). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN   &    |- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- C < T   &    |- A < B   =>    |- ( ( T x. A ) + C ) < ( ( T x. B ) + D )
Theorem	le9lt10 9369	A "decimal digit" (i.e. a nonnegative integer less than or equal to 9) is less then 10. (Contributed by AV, 8-Sep-2021.)
|- A e. NN0   &    |- A <_ 9   =>    |- A < ; 1 0
Theorem	declt 9370	Comparing two decimal integers (equal higher places). (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN   &    |- B < C   =>    |- ; A B < ; A C
Theorem	decltc 9371	Comparing two decimal integers (unequal higher places). (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- C < ; 1 0   &    |- A < B   =>    |- ; A C < ; B D
Theorem	declth 9372	Comparing two decimal integers (unequal higher places). (Contributed by AV, 8-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- C <_ 9   &    |- A < B   =>    |- ; A C < ; B D
Theorem	decsuc 9373	The successor of a decimal integer (no carry). (Contributed by Mario Carneiro, 17-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- ( B + 1 ) = C   &    |- N = ; A B   =>    |- ( N + 1 ) = ; A C
Theorem	3declth 9374	Comparing two decimal integers with three "digits" (unequal higher places). (Contributed by AV, 8-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- E e. NN0   &    |- F e. NN0   &    |- A < B   &    |- C <_ 9   &    |- E <_ 9   =>    |- ;; A C E < ;; B D F
Theorem	3decltc 9375	Comparing two decimal integers with three "digits" (unequal higher places). (Contributed by AV, 15-Jun-2021.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- E e. NN0   &    |- F e. NN0   &    |- A < B   &    |- C < ; 1 0   &    |- E < ; 1 0   =>    |- ;; A C E < ;; B D F
Theorem	decle 9376	Comparing two decimal integers (equal higher places). (Contributed by AV, 17-Aug-2021.) (Revised by AV, 8-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- B <_ C   =>    |- ; A B <_ ; A C
Theorem	decleh 9377	Comparing two decimal integers (unequal higher places). (Contributed by AV, 17-Aug-2021.) (Revised by AV, 8-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- C <_ 9   &    |- A < B   =>    |- ; A C <_ ; B D
Theorem	declei 9378	Comparing a digit to a decimal integer. (Contributed by AV, 17-Aug-2021.)
|- A e. NN   &    |- B e. NN0   &    |- C e. NN0   &    |- C <_ 9   =>    |- C <_ ; A B
Theorem	numlti 9379	Comparing a digit to a decimal integer. (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN   &    |- A e. NN   &    |- B e. NN0   &    |- C e. NN0   &    |- C < T   =>    |- C < ( ( T x. A ) + B )
Theorem	declti 9380	Comparing a digit to a decimal integer. (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN   &    |- B e. NN0   &    |- C e. NN0   &    |- C < ; 1 0   =>    |- C < ; A B
Theorem	decltdi 9381	Comparing a digit to a decimal integer. (Contributed by AV, 8-Sep-2021.)
|- A e. NN   &    |- B e. NN0   &    |- C e. NN0   &    |- C <_ 9   =>    |- C < ; A B
Theorem	numsucc 9382	The successor of a decimal integer (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- Y e. NN0   &    |- T = ( Y + 1 )   &    |- A e. NN0   &    |- ( A + 1 ) = B   &    |- N = ( ( T x. A ) + Y )   =>    |- ( N + 1 ) = ( ( T x. B ) + 0 )
Theorem	decsucc 9383	The successor of a decimal integer (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- ( A + 1 ) = B   &    |- N = ; A 9   =>    |- ( N + 1 ) = ; B 0
Theorem	1e0p1 9384	The successor of zero. (Contributed by Mario Carneiro, 18-Feb-2014.)
|- 1 = ( 0 + 1 )
Theorem	dec10p 9385	Ten plus an integer. (Contributed by Mario Carneiro, 19-Apr-2015.) (Revised by AV, 6-Sep-2021.)
|- (; 1 0 + A ) = ; 1 A
Theorem	numma 9386	Perform a multiply-add of two decimal integers M and N against a fixed multiplicand P (no carry). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ( ( T x. A ) + B )   &    |- N = ( ( T x. C ) + D )   &    |- P e. NN0   &    |- ( ( A x. P ) + C ) = E   &    |- ( ( B x. P ) + D ) = F   =>    |- ( ( M x. P ) + N ) = ( ( T x. E ) + F )
Theorem	nummac 9387	Perform a multiply-add of two decimal integers M and N against a fixed multiplicand P (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ( ( T x. A ) + B )   &    |- N = ( ( T x. C ) + D )   &    |- P e. NN0   &    |- F e. NN0   &    |- G e. NN0   &    |- ( ( A x. P ) + ( C + G ) ) = E   &    |- ( ( B x. P ) + D ) = ( ( T x. G ) + F )   =>    |- ( ( M x. P ) + N ) = ( ( T x. E ) + F )
Theorem	numma2c 9388	Perform a multiply-add of two decimal integers M and N against a fixed multiplicand P (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ( ( T x. A ) + B )   &    |- N = ( ( T x. C ) + D )   &    |- P e. NN0   &    |- F e. NN0   &    |- G e. NN0   &    |- ( ( P x. A ) + ( C + G ) ) = E   &    |- ( ( P x. B ) + D ) = ( ( T x. G ) + F )   =>    |- ( ( P x. M ) + N ) = ( ( T x. E ) + F )
Theorem	numadd 9389	Add two decimal integers M and N (no carry). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ( ( T x. A ) + B )   &    |- N = ( ( T x. C ) + D )   &    |- ( A + C ) = E   &    |- ( B + D ) = F   =>    |- ( M + N ) = ( ( T x. E ) + F )
Theorem	numaddc 9390	Add two decimal integers M and N (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ( ( T x. A ) + B )   &    |- N = ( ( T x. C ) + D )   &    |- F e. NN0   &    |- ( ( A + C ) + 1 ) = E   &    |- ( B + D ) = ( ( T x. 1 ) + F )   =>    |- ( M + N ) = ( ( T x. E ) + F )
Theorem	nummul1c 9391	The product of a decimal integer with a number. (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- P e. NN0   &    |- A e. NN0   &    |- B e. NN0   &    |- N = ( ( T x. A ) + B )   &    |- D e. NN0   &    |- E e. NN0   &    |- ( ( A x. P ) + E ) = C   &    |- ( B x. P ) = ( ( T x. E ) + D )   =>    |- ( N x. P ) = ( ( T x. C ) + D )
Theorem	nummul2c 9392	The product of a decimal integer with a number (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.)
|- T e. NN0   &    |- P e. NN0   &    |- A e. NN0   &    |- B e. NN0   &    |- N = ( ( T x. A ) + B )   &    |- D e. NN0   &    |- E e. NN0   &    |- ( ( P x. A ) + E ) = C   &    |- ( P x. B ) = ( ( T x. E ) + D )   =>    |- ( P x. N ) = ( ( T x. C ) + D )
Theorem	decma 9393	Perform a multiply-add of two numerals M and N against a fixed multiplicand P (no carry). (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ; A B   &    |- N = ; C D   &    |- P e. NN0   &    |- ( ( A x. P ) + C ) = E   &    |- ( ( B x. P ) + D ) = F   =>    |- ( ( M x. P ) + N ) = ; E F
Theorem	decmac 9394	Perform a multiply-add of two numerals M and N against a fixed multiplicand P (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ; A B   &    |- N = ; C D   &    |- P e. NN0   &    |- F e. NN0   &    |- G e. NN0   &    |- ( ( A x. P ) + ( C + G ) ) = E   &    |- ( ( B x. P ) + D ) = ; G F   =>    |- ( ( M x. P ) + N ) = ; E F
Theorem	decma2c 9395	Perform a multiply-add of two numerals M and N against a fixed multiplier P (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ; A B   &    |- N = ; C D   &    |- P e. NN0   &    |- F e. NN0   &    |- G e. NN0   &    |- ( ( P x. A ) + ( C + G ) ) = E   &    |- ( ( P x. B ) + D ) = ; G F   =>    |- ( ( P x. M ) + N ) = ; E F
Theorem	decadd 9396	Add two numerals M and N (no carry). (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ; A B   &    |- N = ; C D   &    |- ( A + C ) = E   &    |- ( B + D ) = F   =>    |- ( M + N ) = ; E F
Theorem	decaddc 9397	Add two numerals M and N (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ; A B   &    |- N = ; C D   &    |- ( ( A + C ) + 1 ) = E   &    |- F e. NN0   &    |- ( B + D ) = ; 1 F   =>    |- ( M + N ) = ; E F
Theorem	decaddc2 9398	Add two numerals M and N (with carry). (Contributed by Mario Carneiro, 18-Feb-2014.) (Revised by AV, 6-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- C e. NN0   &    |- D e. NN0   &    |- M = ; A B   &    |- N = ; C D   &    |- ( ( A + C ) + 1 ) = E   &    |- ( B + D ) = ; 1 0   =>    |- ( M + N ) = ; E 0
Theorem	decrmanc 9399	Perform a multiply-add of two numerals M and N against a fixed multiplicand P (no carry). (Contributed by AV, 16-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- N e. NN0   &    |- M = ; A B   &    |- P e. NN0   &    |- ( A x. P ) = E   &    |- ( ( B x. P ) + N ) = F   =>    |- ( ( M x. P ) + N ) = ; E F
Theorem	decrmac 9400	Perform a multiply-add of two numerals M and N against a fixed multiplicand P (with carry). (Contributed by AV, 16-Sep-2021.)
|- A e. NN0   &    |- B e. NN0   &    |- N e. NN0   &    |- M = ; A B   &    |- P e. NN0   &    |- F e. NN0   &    |- G e. NN0   &    |- ( ( A x. P ) + G ) = E   &    |- ( ( B x. P ) + N ) = ; G F   =>    |- ( ( M x. P ) + N ) = ; E F