Metamath Proof Explorer


Theorem 4finon

Description: 4 is a finite ordinal. See 1onn . (Contributed by RP, 27-Sep-2023)

Ref Expression
Assertion 4finon ⊢ 4 𝑜 ∈ On ∩ Fin

Proof

Step Hyp Ref Expression
1 4onn ⊢ 4 𝑜 ∈ ω
2 onfin2 ⊢ ω = On ∩ Fin
3 1 2 eleqtri ⊢ 4 𝑜 ∈ On ∩ Fin