Theorem nffr 5604

Description: Bound-variable hypothesis builder for well-founded relations. (Contributed by Stefan O'Rear, 20-Jan-2015.) (Revised by Mario Carneiro, 14-Oct-2016.)

Hypotheses

Ref	Expression
nffr.r	⊢ Ⅎ𝑥𝑅
nffr.a	⊢ Ⅎ𝑥𝐴

Assertion

Ref	Expression
nffr	⊢ Ⅎ𝑥 𝑅 Fr 𝐴

Proof of Theorem nffr

Dummy variables 𝑎 𝑏 𝑐 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-fr 5584	. 2 ⊢ (𝑅 Fr 𝐴 ↔ ∀𝑎((𝑎 ⊆ 𝐴 ∧ 𝑎 ≠ ∅) → ∃𝑏 ∈ 𝑎 ∀𝑐 ∈ 𝑎 ¬ 𝑐𝑅𝑏))
2		nfcv 2898	. . . . . 6 ⊢ Ⅎ𝑥𝑎
3		nffr.a	. . . . . 6 ⊢ Ⅎ𝑥𝐴
4	2, 3	nfss 3914	. . . . 5 ⊢ Ⅎ𝑥 𝑎 ⊆ 𝐴
5		nfv 1916	. . . . 5 ⊢ Ⅎ𝑥 𝑎 ≠ ∅
6	4, 5	nfan 1901	. . . 4 ⊢ Ⅎ𝑥(𝑎 ⊆ 𝐴 ∧ 𝑎 ≠ ∅)
7		nfcv 2898	. . . . . . . 8 ⊢ Ⅎ𝑥𝑐
8		nffr.r	. . . . . . . 8 ⊢ Ⅎ𝑥𝑅
9		nfcv 2898	. . . . . . . 8 ⊢ Ⅎ𝑥𝑏
10	7, 8, 9	nfbr 5132	. . . . . . 7 ⊢ Ⅎ𝑥 𝑐𝑅𝑏
11	10	nfn 1859	. . . . . 6 ⊢ Ⅎ𝑥 ¬ 𝑐𝑅𝑏
12	2, 11	nfralw 3284	. . . . 5 ⊢ Ⅎ𝑥∀𝑐 ∈ 𝑎 ¬ 𝑐𝑅𝑏
13	2, 12	nfrexw 3285	. . . 4 ⊢ Ⅎ𝑥∃𝑏 ∈ 𝑎 ∀𝑐 ∈ 𝑎 ¬ 𝑐𝑅𝑏
14	6, 13	nfim 1898	. . 3 ⊢ Ⅎ𝑥((𝑎 ⊆ 𝐴 ∧ 𝑎 ≠ ∅) → ∃𝑏 ∈ 𝑎 ∀𝑐 ∈ 𝑎 ¬ 𝑐𝑅𝑏)
15	14	nfal 2328	. 2 ⊢ Ⅎ𝑥∀𝑎((𝑎 ⊆ 𝐴 ∧ 𝑎 ≠ ∅) → ∃𝑏 ∈ 𝑎 ∀𝑐 ∈ 𝑎 ¬ 𝑐𝑅𝑏)
16	1, 15	nfxfr 1855	1 ⊢ Ⅎ𝑥 𝑅 Fr 𝐴

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 395  ∀wal 1540  Ⅎwnf 1785  Ⅎwnfc 2883   ≠ wne 2932  ∀wral 3051  ∃wrex 3061   ⊆ wss 3889  ∅c0 4273   class class class wbr 5085   Fr wfr 5581

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2708

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-clab 2715  df-cleq 2728  df-clel 2811  df-nfc 2885  df-ral 3052  df-rex 3062  df-rab 3390  df-v 3431  df-dif 3892  df-un 3894  df-ss 3906  df-nul 4274  df-if 4467  df-sn 4568  df-pr 4570  df-op 4574  df-br 5086  df-fr 5584

This theorem is referenced by:  nfwe  5606  weiunfr  36649