Metamath Proof Explorer


Theorem 2aryfvalel

Description: A binary (endo)function on a set X . (Contributed by AV, 20-May-2024)

Ref Expression
Assertion 2aryfvalel ⊢ X ∈ V → F ∈ 2 -aryF X ↔ F : X 0 1 ⟶ X

Proof

Step Hyp Ref Expression
1 2nn0 ⊢ 2 ∈ ℕ 0
2 fzo0to2pr ⊢ 0 ..^ 2 = 0 1
3 2 eqcomi ⊢ 0 1 = 0 ..^ 2
4 3 naryfvalel ⊢ 2 ∈ ℕ 0 ∧ X ∈ V → F ∈ 2 -aryF X ↔ F : X 0 1 ⟶ X
5 1 4 mpan ⊢ X ∈ V → F ∈ 2 -aryF X ↔ F : X 0 1 ⟶ X