Metamath Proof Explorer


Theorem efgmf

Description: The formal inverse operation is an endofunction on the generating set. (Contributed by Mario Carneiro, 27-Sep-2015)

Ref Expression
Hypothesis efgmval.m 𝑀 = ( 𝑦𝐼 , 𝑧 ∈ 2o ↦ ⟨ 𝑦 , ( 1o𝑧 ) ⟩ )
Assertion efgmf 𝑀 : ( 𝐼 × 2o ) ⟶ ( 𝐼 × 2o )

Proof

Step Hyp Ref Expression
1 efgmval.m 𝑀 = ( 𝑦𝐼 , 𝑧 ∈ 2o ↦ ⟨ 𝑦 , ( 1o𝑧 ) ⟩ )
2 2oconcl ( 𝑧 ∈ 2o → ( 1o𝑧 ) ∈ 2o )
3 opelxpi ( ( 𝑦𝐼 ∧ ( 1o𝑧 ) ∈ 2o ) → ⟨ 𝑦 , ( 1o𝑧 ) ⟩ ∈ ( 𝐼 × 2o ) )
4 2 3 sylan2 ( ( 𝑦𝐼𝑧 ∈ 2o ) → ⟨ 𝑦 , ( 1o𝑧 ) ⟩ ∈ ( 𝐼 × 2o ) )
5 4 rgen2 𝑦𝐼𝑧 ∈ 2o𝑦 , ( 1o𝑧 ) ⟩ ∈ ( 𝐼 × 2o )
6 1 fmpo ( ∀ 𝑦𝐼𝑧 ∈ 2o𝑦 , ( 1o𝑧 ) ⟩ ∈ ( 𝐼 × 2o ) ↔ 𝑀 : ( 𝐼 × 2o ) ⟶ ( 𝐼 × 2o ) )
7 5 6 mpbi 𝑀 : ( 𝐼 × 2o ) ⟶ ( 𝐼 × 2o )