Metamath Proof Explorer


Theorem numsuc

Description: The successor of a decimal integer (no carry). (Contributed by Mario Carneiro, 18-Feb-2014)

Ref Expression
Hypotheses numnncl.1
|- T e. NN0
numnncl.2
|- A e. NN0
numcl.2
|- B e. NN0
numsuc.4
|- ( B + 1 ) = C
numsuc.5
|- N = ( ( T x. A ) + B )
Assertion numsuc
|- ( N + 1 ) = ( ( T x. A ) + C )

Proof

Step Hyp Ref Expression
1 numnncl.1
 |-  T e. NN0
2 numnncl.2
 |-  A e. NN0
3 numcl.2
 |-  B e. NN0
4 numsuc.4
 |-  ( B + 1 ) = C
5 numsuc.5
 |-  N = ( ( T x. A ) + B )
6 5 oveq1i
 |-  ( N + 1 ) = ( ( ( T x. A ) + B ) + 1 )
7 1 2 nn0mulcli
 |-  ( T x. A ) e. NN0
8 7 nn0cni
 |-  ( T x. A ) e. CC
9 3 nn0cni
 |-  B e. CC
10 ax-1cn
 |-  1 e. CC
11 8 9 10 addassi
 |-  ( ( ( T x. A ) + B ) + 1 ) = ( ( T x. A ) + ( B + 1 ) )
12 4 oveq2i
 |-  ( ( T x. A ) + ( B + 1 ) ) = ( ( T x. A ) + C )
13 6 11 12 3eqtri
 |-  ( N + 1 ) = ( ( T x. A ) + C )