Metamath Proof Explorer


Theorem naryrcl

Description: Reverse closure for n-ary (endo)functions. (Contributed by AV, 14-May-2024)

Ref Expression
Hypothesis naryfval.i 𝐼 = ( 0 ..^ 𝑁 )
Assertion naryrcl ( 𝐹 ∈ ( 𝑁 -aryF 𝑋 ) → ( 𝑁 ∈ ℕ0𝑋 ∈ V ) )

Proof

Step Hyp Ref Expression
1 naryfval.i 𝐼 = ( 0 ..^ 𝑁 )
2 df-naryf -aryF = ( 𝑥 ∈ ℕ0 , 𝑛 ∈ V ↦ ( 𝑛m ( 𝑛m ( 0 ..^ 𝑥 ) ) ) )
3 2 elmpocl ( 𝐹 ∈ ( 𝑁 -aryF 𝑋 ) → ( 𝑁 ∈ ℕ0𝑋 ∈ V ) )