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