Theorem 6nn0

Description: 6 is a nonnegative integer. (Contributed by Mario Carneiro, 19-Apr-2015)

	Ref	Expression
Assertion	6nn0	|- 6 e. NN0

Proof

Step	Hyp	Ref	Expression
1		6nn	|- 6 e. NN
2	1	nnnn0i	|- 6 e. NN0