Metamath Proof Explorer


Theorem bnj1518

Description: Technical lemma for bnj1500 . 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 bnj1518.1 B = d | d A x d pred x A R d
bnj1518.2 Y = x f pred x A R
bnj1518.3 C = f | d B f Fn d x d f x = G Y
bnj1518.4 F = C
bnj1518.5 φ R FrSe A x A
bnj1518.6 ψ φ f C x dom f
Assertion bnj1518 ψ d ψ

Proof

Step Hyp Ref Expression
1 bnj1518.1 B = d | d A x d pred x A R d
2 bnj1518.2 Y = x f pred x A R
3 bnj1518.3 C = f | d B f Fn d x d f x = G Y
4 bnj1518.4 F = C
5 bnj1518.5 φ R FrSe A x A
6 bnj1518.6 ψ φ f C x dom f
7 nfv d φ
8 nfre1 d d B f Fn d x d f x = G Y
9 8 nfab _ d f | d B f Fn d x d f x = G Y
10 3 9 nfcxfr _ d C
11 10 nfcri d f C
12 nfv d x dom f
13 7 11 12 nf3an d φ f C x dom f
14 6 13 nfxfr d ψ
15 14 nf5ri ψ d ψ