Metamath Proof Explorer


Theorem nfpo

Description: Bound-variable hypothesis builder for partial orders. (Contributed by Stefan O'Rear, 20-Jan-2015)

Ref Expression
Hypotheses nfpo.r _ x R
nfpo.a _ x A
Assertion nfpo x R Po A

Proof

Step Hyp Ref Expression
1 nfpo.r _ x R
2 nfpo.a _ x A
3 df-po R Po A a A b A c A ¬ a R a a R b b R c a R c
4 nfcv _ x a
5 4 1 4 nfbr x a R a
6 5 nfn x ¬ a R a
7 nfcv _ x b
8 4 1 7 nfbr x a R b
9 nfcv _ x c
10 7 1 9 nfbr x b R c
11 8 10 nfan x a R b b R c
12 4 1 9 nfbr x a R c
13 11 12 nfim x a R b b R c a R c
14 6 13 nfan x ¬ a R a a R b b R c a R c
15 2 14 nfralw x c A ¬ a R a a R b b R c a R c
16 2 15 nfralw x b A c A ¬ a R a a R b b R c a R c
17 2 16 nfralw x a A b A c A ¬ a R a a R b b R c a R c
18 3 17 nfxfr x R Po A