Metamath Proof Explorer


Theorem 2oexOLD

Description: Obsolete version of 2oex as of 19-Sep-2024. (Contributed by BJ, 6-Apr-2019) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Assertion 2oexOLD 2 𝑜 V

Proof

Step Hyp Ref Expression
1 df-2o 2 𝑜 = suc 1 𝑜
2 1oex 1 𝑜 V
3 2 sucex suc 1 𝑜 V
4 1 3 eqeltri 2 𝑜 V