Theorem 4t4e16

Description: 4 times 4 equals 16. (Contributed by Mario Carneiro, 19-Apr-2015)

	Ref	Expression
Assertion	4t4e16	|- ( 4 x. 4 ) = ; 1 6

Proof

Step	Hyp	Ref	Expression
1		4nn0	|- 4 e. NN0
2		3nn0	|- 3 e. NN0
3		df-4	|- 4 = ( 3 + 1 )
4		4t3e12	|- ( 4 x. 3 ) = ; 1 2
5		1nn0	|- 1 e. NN0
6		2nn0	|- 2 e. NN0
7		eqid	|- ; 1 2 = ; 1 2
8		4cn	|- 4 e. CC
9		2cn	|- 2 e. CC
10		4p2e6	|- ( 4 + 2 ) = 6
11	8 9 10	addcomli	|- ( 2 + 4 ) = 6
12	5 6 1 7 11	decaddi	|- ( ; 1 2 + 4 ) = ; 1 6
13	1 2 3 4 12	4t3lem	|- ( 4 x. 4 ) = ; 1 6