Metamath Proof Explorer


Theorem bnj1309

Description: Technical lemma for bnj60 . 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
Hypothesis bnj1309.1 B = d | d A x d pred x A R d
Assertion bnj1309 w B x w B

Proof

Step Hyp Ref Expression
1 bnj1309.1 B = d | d A x d pred x A R d
2 hbra1 x d pred x A R d x x d pred x A R d
3 2 bnj1352 d A x d pred x A R d x d A x d pred x A R d
4 3 hbab w d | d A x d pred x A R d x w d | d A x d pred x A R d
5 1 4 hbxfreq w B x w B