Metamath Proof Explorer


Theorem bnj911

Description: Technical lemma for bnj69 . 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 bnj911.1 ( 𝜑 ↔ ( 𝑓 ‘ ∅ ) = pred ( 𝑋 , 𝐴 , 𝑅 ) )
bnj911.2 ( 𝜓 ↔ ∀ 𝑖 ∈ ω ( suc 𝑖𝑛 → ( 𝑓 ‘ suc 𝑖 ) = 𝑦 ∈ ( 𝑓𝑖 ) pred ( 𝑦 , 𝐴 , 𝑅 ) ) )
Assertion bnj911 ( ( 𝑓 Fn 𝑛𝜑𝜓 ) → ∀ 𝑖 ( 𝑓 Fn 𝑛𝜑𝜓 ) )

Proof

Step Hyp Ref Expression
1 bnj911.1 ( 𝜑 ↔ ( 𝑓 ‘ ∅ ) = pred ( 𝑋 , 𝐴 , 𝑅 ) )
2 bnj911.2 ( 𝜓 ↔ ∀ 𝑖 ∈ ω ( suc 𝑖𝑛 → ( 𝑓 ‘ suc 𝑖 ) = 𝑦 ∈ ( 𝑓𝑖 ) pred ( 𝑦 , 𝐴 , 𝑅 ) ) )
3 2 bnj1095 ( 𝜓 → ∀ 𝑖 𝜓 )
4 3 bnj1350 ( ( 𝑓 Fn 𝑛𝜑𝜓 ) → ∀ 𝑖 ( 𝑓 Fn 𝑛𝜑𝜓 ) )