Theorem 1zzd

Description: One is an integer, deduction form. (Contributed by David A. Wheeler, 6-Dec-2018)

	Ref	Expression
Assertion	1zzd	$$⊢\phi \to 1\in \mathbb{Z}$$

Proof

Step	Hyp	Ref	Expression
1		1z	$$⊢1\in \mathbb{Z}$$
2	1	a1i	$$⊢\phi \to 1\in \mathbb{Z}$$