Metamath Proof Explorer


Theorem bnj1040

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 bnj1040.1 ( 𝜑′[ 𝑗 / 𝑖 ] 𝜑 )
bnj1040.2 ( 𝜓′[ 𝑗 / 𝑖 ] 𝜓 )
bnj1040.3 ( 𝜒 ↔ ( 𝑛𝐷𝑓 Fn 𝑛𝜑𝜓 ) )
bnj1040.4 ( 𝜒′[ 𝑗 / 𝑖 ] 𝜒 )
Assertion bnj1040 ( 𝜒′ ↔ ( 𝑛𝐷𝑓 Fn 𝑛𝜑′𝜓′ ) )

Proof

Step Hyp Ref Expression
1 bnj1040.1 ( 𝜑′[ 𝑗 / 𝑖 ] 𝜑 )
2 bnj1040.2 ( 𝜓′[ 𝑗 / 𝑖 ] 𝜓 )
3 bnj1040.3 ( 𝜒 ↔ ( 𝑛𝐷𝑓 Fn 𝑛𝜑𝜓 ) )
4 bnj1040.4 ( 𝜒′[ 𝑗 / 𝑖 ] 𝜒 )
5 3 sbcbii ( [ 𝑗 / 𝑖 ] 𝜒[ 𝑗 / 𝑖 ] ( 𝑛𝐷𝑓 Fn 𝑛𝜑𝜓 ) )
6 df-bnj17 ( ( [ 𝑗 / 𝑖 ] 𝑛𝐷[ 𝑗 / 𝑖 ] 𝑓 Fn 𝑛[ 𝑗 / 𝑖 ] 𝜑[ 𝑗 / 𝑖 ] 𝜓 ) ↔ ( ( [ 𝑗 / 𝑖 ] 𝑛𝐷[ 𝑗 / 𝑖 ] 𝑓 Fn 𝑛[ 𝑗 / 𝑖 ] 𝜑 ) ∧ [ 𝑗 / 𝑖 ] 𝜓 ) )
7 vex 𝑗 ∈ V
8 7 bnj525 ( [ 𝑗 / 𝑖 ] 𝑛𝐷𝑛𝐷 )
9 8 bicomi ( 𝑛𝐷[ 𝑗 / 𝑖 ] 𝑛𝐷 )
10 7 bnj525 ( [ 𝑗 / 𝑖 ] 𝑓 Fn 𝑛𝑓 Fn 𝑛 )
11 10 bicomi ( 𝑓 Fn 𝑛[ 𝑗 / 𝑖 ] 𝑓 Fn 𝑛 )
12 9 11 1 2 bnj887 ( ( 𝑛𝐷𝑓 Fn 𝑛𝜑′𝜓′ ) ↔ ( [ 𝑗 / 𝑖 ] 𝑛𝐷[ 𝑗 / 𝑖 ] 𝑓 Fn 𝑛[ 𝑗 / 𝑖 ] 𝜑[ 𝑗 / 𝑖 ] 𝜓 ) )
13 df-bnj17 ( ( 𝑛𝐷𝑓 Fn 𝑛𝜑𝜓 ) ↔ ( ( 𝑛𝐷𝑓 Fn 𝑛𝜑 ) ∧ 𝜓 ) )
14 13 sbcbii ( [ 𝑗 / 𝑖 ] ( 𝑛𝐷𝑓 Fn 𝑛𝜑𝜓 ) ↔ [ 𝑗 / 𝑖 ] ( ( 𝑛𝐷𝑓 Fn 𝑛𝜑 ) ∧ 𝜓 ) )
15 sbcan ( [ 𝑗 / 𝑖 ] ( ( 𝑛𝐷𝑓 Fn 𝑛𝜑 ) ∧ 𝜓 ) ↔ ( [ 𝑗 / 𝑖 ] ( 𝑛𝐷𝑓 Fn 𝑛𝜑 ) ∧ [ 𝑗 / 𝑖 ] 𝜓 ) )
16 sbc3an ( [ 𝑗 / 𝑖 ] ( 𝑛𝐷𝑓 Fn 𝑛𝜑 ) ↔ ( [ 𝑗 / 𝑖 ] 𝑛𝐷[ 𝑗 / 𝑖 ] 𝑓 Fn 𝑛[ 𝑗 / 𝑖 ] 𝜑 ) )
17 16 anbi1i ( ( [ 𝑗 / 𝑖 ] ( 𝑛𝐷𝑓 Fn 𝑛𝜑 ) ∧ [ 𝑗 / 𝑖 ] 𝜓 ) ↔ ( ( [ 𝑗 / 𝑖 ] 𝑛𝐷[ 𝑗 / 𝑖 ] 𝑓 Fn 𝑛[ 𝑗 / 𝑖 ] 𝜑 ) ∧ [ 𝑗 / 𝑖 ] 𝜓 ) )
18 14 15 17 3bitri ( [ 𝑗 / 𝑖 ] ( 𝑛𝐷𝑓 Fn 𝑛𝜑𝜓 ) ↔ ( ( [ 𝑗 / 𝑖 ] 𝑛𝐷[ 𝑗 / 𝑖 ] 𝑓 Fn 𝑛[ 𝑗 / 𝑖 ] 𝜑 ) ∧ [ 𝑗 / 𝑖 ] 𝜓 ) )
19 6 12 18 3bitr4ri ( [ 𝑗 / 𝑖 ] ( 𝑛𝐷𝑓 Fn 𝑛𝜑𝜓 ) ↔ ( 𝑛𝐷𝑓 Fn 𝑛𝜑′𝜓′ ) )
20 4 5 19 3bitri ( 𝜒′ ↔ ( 𝑛𝐷𝑓 Fn 𝑛𝜑′𝜓′ ) )