Metamath Proof Explorer


Theorem suceq

Description: Equality of successors. (Contributed by NM, 30-Aug-1993) (Proof shortened by Andrew Salmon, 25-Jul-2011)

Ref Expression
Assertion suceq ⊢ A = B → suc ⁡ A = suc ⁡ B

Proof

Step Hyp Ref Expression
1 id ⊢ A = B → A = B
2 1 suceqd ⊢ A = B → suc ⁡ A = suc ⁡ B