Metamath Proof Explorer


Theorem bnj548

Description: Technical lemma for bnj852 . 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 bnj548.1 No typesetting found for |- ( ta <-> ( f Fn m /\ ph' /\ ps' ) ) with typecode |-
bnj548.2 B = y f i pred y A R
bnj548.3 K = y G i pred y A R
bnj548.4 G = f m C
bnj548.5 R FrSe A τ σ G Fn n
Assertion bnj548 R FrSe A τ σ i m B = K

Proof

Step Hyp Ref Expression
1 bnj548.1 Could not format ( ta <-> ( f Fn m /\ ph' /\ ps' ) ) : No typesetting found for |- ( ta <-> ( f Fn m /\ ph' /\ ps' ) ) with typecode |-
2 bnj548.2 B = y f i pred y A R
3 bnj548.3 K = y G i pred y A R
4 bnj548.4 G = f m C
5 bnj548.5 R FrSe A τ σ G Fn n
6 5 fnfund R FrSe A τ σ Fun G
7 6 adantr R FrSe A τ σ i m Fun G
8 1 simp1bi τ f Fn m
9 fndm f Fn m dom f = m
10 eleq2 dom f = m i dom f i m
11 10 biimpar dom f = m i m i dom f
12 9 11 sylan f Fn m i m i dom f
13 8 12 sylan τ i m i dom f
14 13 3ad2antl2 R FrSe A τ σ i m i dom f
15 7 14 jca R FrSe A τ σ i m Fun G i dom f
16 4 bnj931 f G
17 15 16 jctil R FrSe A τ σ i m f G Fun G i dom f
18 3anan12 Fun G f G i dom f f G Fun G i dom f
19 17 18 sylibr R FrSe A τ σ i m Fun G f G i dom f
20 funssfv Fun G f G i dom f G i = f i
21 iuneq1 G i = f i y G i pred y A R = y f i pred y A R
22 21 eqcomd G i = f i y f i pred y A R = y G i pred y A R
23 22 2 3 3eqtr4g G i = f i B = K
24 19 20 23 3syl R FrSe A τ σ i m B = K