Metamath Proof Explorer


Theorem bnj1529

Description: Technical lemma for bnj1522 . This lemma may no longer be used or have become an indirect lemma of the theorem in question (i.e. a lemma of a lemma... of the theorem). (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

Ref Expression
Hypotheses bnj1529.1 ( 𝜒 → ∀ 𝑥𝐴 ( 𝐹𝑥 ) = ( 𝐺 ‘ ⟨ 𝑥 , ( 𝐹 ↾ pred ( 𝑥 , 𝐴 , 𝑅 ) ) ⟩ ) )
bnj1529.2 ( 𝑤𝐹 → ∀ 𝑥 𝑤𝐹 )
Assertion bnj1529 ( 𝜒 → ∀ 𝑦𝐴 ( 𝐹𝑦 ) = ( 𝐺 ‘ ⟨ 𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩ ) )

Proof

Step Hyp Ref Expression
1 bnj1529.1 ( 𝜒 → ∀ 𝑥𝐴 ( 𝐹𝑥 ) = ( 𝐺 ‘ ⟨ 𝑥 , ( 𝐹 ↾ pred ( 𝑥 , 𝐴 , 𝑅 ) ) ⟩ ) )
2 bnj1529.2 ( 𝑤𝐹 → ∀ 𝑥 𝑤𝐹 )
3 nfv 𝑦 ( 𝐹𝑥 ) = ( 𝐺 ‘ ⟨ 𝑥 , ( 𝐹 ↾ pred ( 𝑥 , 𝐴 , 𝑅 ) ) ⟩ )
4 2 nfcii 𝑥 𝐹
5 nfcv 𝑥 𝑦
6 4 5 nffv 𝑥 ( 𝐹𝑦 )
7 nfcv 𝑥 𝐺
8 nfcv 𝑥 pred ( 𝑦 , 𝐴 , 𝑅 )
9 4 8 nfres 𝑥 ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) )
10 5 9 nfop 𝑥𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩
11 7 10 nffv 𝑥 ( 𝐺 ‘ ⟨ 𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩ )
12 6 11 nfeq 𝑥 ( 𝐹𝑦 ) = ( 𝐺 ‘ ⟨ 𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩ )
13 fveq2 ( 𝑥 = 𝑦 → ( 𝐹𝑥 ) = ( 𝐹𝑦 ) )
14 id ( 𝑥 = 𝑦𝑥 = 𝑦 )
15 bnj602 ( 𝑥 = 𝑦 → pred ( 𝑥 , 𝐴 , 𝑅 ) = pred ( 𝑦 , 𝐴 , 𝑅 ) )
16 15 reseq2d ( 𝑥 = 𝑦 → ( 𝐹 ↾ pred ( 𝑥 , 𝐴 , 𝑅 ) ) = ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) )
17 14 16 opeq12d ( 𝑥 = 𝑦 → ⟨ 𝑥 , ( 𝐹 ↾ pred ( 𝑥 , 𝐴 , 𝑅 ) ) ⟩ = ⟨ 𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩ )
18 17 fveq2d ( 𝑥 = 𝑦 → ( 𝐺 ‘ ⟨ 𝑥 , ( 𝐹 ↾ pred ( 𝑥 , 𝐴 , 𝑅 ) ) ⟩ ) = ( 𝐺 ‘ ⟨ 𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩ ) )
19 13 18 eqeq12d ( 𝑥 = 𝑦 → ( ( 𝐹𝑥 ) = ( 𝐺 ‘ ⟨ 𝑥 , ( 𝐹 ↾ pred ( 𝑥 , 𝐴 , 𝑅 ) ) ⟩ ) ↔ ( 𝐹𝑦 ) = ( 𝐺 ‘ ⟨ 𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩ ) ) )
20 3 12 19 cbvralw ( ∀ 𝑥𝐴 ( 𝐹𝑥 ) = ( 𝐺 ‘ ⟨ 𝑥 , ( 𝐹 ↾ pred ( 𝑥 , 𝐴 , 𝑅 ) ) ⟩ ) ↔ ∀ 𝑦𝐴 ( 𝐹𝑦 ) = ( 𝐺 ‘ ⟨ 𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩ ) )
21 1 20 sylib ( 𝜒 → ∀ 𝑦𝐴 ( 𝐹𝑦 ) = ( 𝐺 ‘ ⟨ 𝑦 , ( 𝐹 ↾ pred ( 𝑦 , 𝐴 , 𝑅 ) ) ⟩ ) )