Metamath Proof Explorer


Theorem naryfvalel

Description: An n-ary (endo)function on a set X . (Contributed by AV, 14-May-2024)

Ref Expression
Hypothesis naryfval.i 𝐼 = ( 0 ..^ 𝑁 )
Assertion naryfvalel ( ( 𝑁 ∈ ℕ0𝑋𝑉 ) → ( 𝐹 ∈ ( 𝑁 -aryF 𝑋 ) ↔ 𝐹 : ( 𝑋m 𝐼 ) ⟶ 𝑋 ) )

Proof

Step Hyp Ref Expression
1 naryfval.i 𝐼 = ( 0 ..^ 𝑁 )
2 1 naryfval ( 𝑁 ∈ ℕ0 → ( 𝑁 -aryF 𝑋 ) = ( 𝑋m ( 𝑋m 𝐼 ) ) )
3 2 eleq2d ( 𝑁 ∈ ℕ0 → ( 𝐹 ∈ ( 𝑁 -aryF 𝑋 ) ↔ 𝐹 ∈ ( 𝑋m ( 𝑋m 𝐼 ) ) ) )
4 ovex ( 𝑋m 𝐼 ) ∈ V
5 elmapg ( ( 𝑋𝑉 ∧ ( 𝑋m 𝐼 ) ∈ V ) → ( 𝐹 ∈ ( 𝑋m ( 𝑋m 𝐼 ) ) ↔ 𝐹 : ( 𝑋m 𝐼 ) ⟶ 𝑋 ) )
6 4 5 mpan2 ( 𝑋𝑉 → ( 𝐹 ∈ ( 𝑋m ( 𝑋m 𝐼 ) ) ↔ 𝐹 : ( 𝑋m 𝐼 ) ⟶ 𝑋 ) )
7 3 6 sylan9bb ( ( 𝑁 ∈ ℕ0𝑋𝑉 ) → ( 𝐹 ∈ ( 𝑁 -aryF 𝑋 ) ↔ 𝐹 : ( 𝑋m 𝐼 ) ⟶ 𝑋 ) )