Theorem pmtrfinv 18231

Description: A transposition function is an involution. (Contributed by Stefan O'Rear, 22-Aug-2015.)

Hypotheses

Ref	Expression
pmtrrn.t	⊢ 𝑇 = (pmTrsp‘𝐷)
pmtrrn.r	⊢ 𝑅 = ran 𝑇

Assertion

Ref	Expression
pmtrfinv	⊢ (𝐹 ∈ 𝑅 → (𝐹 ∘ 𝐹) = ( I ↾ 𝐷))

Proof of Theorem pmtrfinv

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		pmtrrn.t	. . . . . . 7 ⊢ 𝑇 = (pmTrsp‘𝐷)
2		pmtrrn.r	. . . . . . 7 ⊢ 𝑅 = ran 𝑇
3		eqid 2825	. . . . . . 7 ⊢ dom (𝐹 ∖ I ) = dom (𝐹 ∖ I )
4	1, 2, 3	pmtrfrn 18228	. . . . . 6 ⊢ (𝐹 ∈ 𝑅 → ((𝐷 ∈ V ∧ dom (𝐹 ∖ I ) ⊆ 𝐷 ∧ dom (𝐹 ∖ I ) ≈ 2o) ∧ 𝐹 = (𝑇‘dom (𝐹 ∖ I ))))
5	4	simpld 490	. . . . 5 ⊢ (𝐹 ∈ 𝑅 → (𝐷 ∈ V ∧ dom (𝐹 ∖ I ) ⊆ 𝐷 ∧ dom (𝐹 ∖ I ) ≈ 2o))
6	1	pmtrf 18225	. . . . 5 ⊢ ((𝐷 ∈ V ∧ dom (𝐹 ∖ I ) ⊆ 𝐷 ∧ dom (𝐹 ∖ I ) ≈ 2o) → (𝑇‘dom (𝐹 ∖ I )):𝐷⟶𝐷)
7	5, 6	syl 17	. . . 4 ⊢ (𝐹 ∈ 𝑅 → (𝑇‘dom (𝐹 ∖ I )):𝐷⟶𝐷)
8	4	simprd 491	. . . . 5 ⊢ (𝐹 ∈ 𝑅 → 𝐹 = (𝑇‘dom (𝐹 ∖ I )))
9	8	feq1d 6263	. . . 4 ⊢ (𝐹 ∈ 𝑅 → (𝐹:𝐷⟶𝐷 ↔ (𝑇‘dom (𝐹 ∖ I )):𝐷⟶𝐷))
10	7, 9	mpbird 249	. . 3 ⊢ (𝐹 ∈ 𝑅 → 𝐹:𝐷⟶𝐷)
11		fco 6295	. . . 4 ⊢ ((𝐹:𝐷⟶𝐷 ∧ 𝐹:𝐷⟶𝐷) → (𝐹 ∘ 𝐹):𝐷⟶𝐷)
12	11	anidms 562	. . 3 ⊢ (𝐹:𝐷⟶𝐷 → (𝐹 ∘ 𝐹):𝐷⟶𝐷)
13		ffn 6278	. . 3 ⊢ ((𝐹 ∘ 𝐹):𝐷⟶𝐷 → (𝐹 ∘ 𝐹) Fn 𝐷)
14	10, 12, 13	3syl 18	. 2 ⊢ (𝐹 ∈ 𝑅 → (𝐹 ∘ 𝐹) Fn 𝐷)
15		fnresi 6241	. . 3 ⊢ ( I ↾ 𝐷) Fn 𝐷
16	15	a1i 11	. 2 ⊢ (𝐹 ∈ 𝑅 → ( I ↾ 𝐷) Fn 𝐷)
17	1, 2, 3	pmtrffv 18229	. . . . . . 7 ⊢ ((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) → (𝐹‘𝑥) = if(𝑥 ∈ dom (𝐹 ∖ I ), ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}), 𝑥))
18		iftrue 4312	. . . . . . 7 ⊢ (𝑥 ∈ dom (𝐹 ∖ I ) → if(𝑥 ∈ dom (𝐹 ∖ I ), ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}), 𝑥) = ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}))
19	17, 18	sylan9eq 2881	. . . . . 6 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → (𝐹‘𝑥) = ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}))
20	19	fveq2d 6437	. . . . 5 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → (𝐹‘(𝐹‘𝑥)) = (𝐹‘∪ (dom (𝐹 ∖ I ) ∖ {𝑥})))
21		simpll 783	. . . . . . 7 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → 𝐹 ∈ 𝑅)
22	5	simp2d 1177	. . . . . . . . 9 ⊢ (𝐹 ∈ 𝑅 → dom (𝐹 ∖ I ) ⊆ 𝐷)
23	22	ad2antrr 717	. . . . . . . 8 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → dom (𝐹 ∖ I ) ⊆ 𝐷)
24		1onn 7986	. . . . . . . . . . . 12 ⊢ 1o ∈ ω
25	24	a1i 11	. . . . . . . . . . 11 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → 1o ∈ ω)
26	5	simp3d 1178	. . . . . . . . . . . . 13 ⊢ (𝐹 ∈ 𝑅 → dom (𝐹 ∖ I ) ≈ 2o)
27		df-2o 7827	. . . . . . . . . . . . 13 ⊢ 2o = suc 1o
28	26, 27	syl6breq 4914	. . . . . . . . . . . 12 ⊢ (𝐹 ∈ 𝑅 → dom (𝐹 ∖ I ) ≈ suc 1o)
29	28	ad2antrr 717	. . . . . . . . . . 11 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → dom (𝐹 ∖ I ) ≈ suc 1o)
30		simpr 479	. . . . . . . . . . 11 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → 𝑥 ∈ dom (𝐹 ∖ I ))
31		dif1en 8462	. . . . . . . . . . 11 ⊢ ((1o ∈ ω ∧ dom (𝐹 ∖ I ) ≈ suc 1o ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → (dom (𝐹 ∖ I ) ∖ {𝑥}) ≈ 1o)
32	25, 29, 30, 31	syl3anc 1494	. . . . . . . . . 10 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → (dom (𝐹 ∖ I ) ∖ {𝑥}) ≈ 1o)
33		en1uniel 8294	. . . . . . . . . 10 ⊢ ((dom (𝐹 ∖ I ) ∖ {𝑥}) ≈ 1o → ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ (dom (𝐹 ∖ I ) ∖ {𝑥}))
34	32, 33	syl 17	. . . . . . . . 9 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ (dom (𝐹 ∖ I ) ∖ {𝑥}))
35	34	eldifad 3810	. . . . . . . 8 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ dom (𝐹 ∖ I ))
36	23, 35	sseldd 3828	. . . . . . 7 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ 𝐷)
37	1, 2, 3	pmtrffv 18229	. . . . . . 7 ⊢ ((𝐹 ∈ 𝑅 ∧ ∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ 𝐷) → (𝐹‘∪ (dom (𝐹 ∖ I ) ∖ {𝑥})) = if(∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ dom (𝐹 ∖ I ), ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}), ∪ (dom (𝐹 ∖ I ) ∖ {𝑥})))
38	21, 36, 37	syl2anc 579	. . . . . 6 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → (𝐹‘∪ (dom (𝐹 ∖ I ) ∖ {𝑥})) = if(∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ dom (𝐹 ∖ I ), ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}), ∪ (dom (𝐹 ∖ I ) ∖ {𝑥})))
39		iftrue 4312	. . . . . . . 8 ⊢ (∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ dom (𝐹 ∖ I ) → if(∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ dom (𝐹 ∖ I ), ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}), ∪ (dom (𝐹 ∖ I ) ∖ {𝑥})) = ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}))
40	35, 39	syl 17	. . . . . . 7 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → if(∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ dom (𝐹 ∖ I ), ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}), ∪ (dom (𝐹 ∖ I ) ∖ {𝑥})) = ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}))
41	26	adantr 474	. . . . . . . 8 ⊢ ((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) → dom (𝐹 ∖ I ) ≈ 2o)
42		en2other2 9145	. . . . . . . . 9 ⊢ ((𝑥 ∈ dom (𝐹 ∖ I ) ∧ dom (𝐹 ∖ I ) ≈ 2o) → ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}) = 𝑥)
43	42	ancoms 452	. . . . . . . 8 ⊢ ((dom (𝐹 ∖ I ) ≈ 2o ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}) = 𝑥)
44	41, 43	sylan 575	. . . . . . 7 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}) = 𝑥)
45	40, 44	eqtrd 2861	. . . . . 6 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → if(∪ (dom (𝐹 ∖ I ) ∖ {𝑥}) ∈ dom (𝐹 ∖ I ), ∪ (dom (𝐹 ∖ I ) ∖ {∪ (dom (𝐹 ∖ I ) ∖ {𝑥})}), ∪ (dom (𝐹 ∖ I ) ∖ {𝑥})) = 𝑥)
46	38, 45	eqtrd 2861	. . . . 5 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → (𝐹‘∪ (dom (𝐹 ∖ I ) ∖ {𝑥})) = 𝑥)
47	20, 46	eqtrd 2861	. . . 4 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ 𝑥 ∈ dom (𝐹 ∖ I )) → (𝐹‘(𝐹‘𝑥)) = 𝑥)
48	10	ffnd 6279	. . . . . . . 8 ⊢ (𝐹 ∈ 𝑅 → 𝐹 Fn 𝐷)
49		fnelnfp 6695	. . . . . . . 8 ⊢ ((𝐹 Fn 𝐷 ∧ 𝑥 ∈ 𝐷) → (𝑥 ∈ dom (𝐹 ∖ I ) ↔ (𝐹‘𝑥) ≠ 𝑥))
50	48, 49	sylan 575	. . . . . . 7 ⊢ ((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) → (𝑥 ∈ dom (𝐹 ∖ I ) ↔ (𝐹‘𝑥) ≠ 𝑥))
51	50	necon2bbid 3042	. . . . . 6 ⊢ ((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) → ((𝐹‘𝑥) = 𝑥 ↔ ¬ 𝑥 ∈ dom (𝐹 ∖ I )))
52	51	biimpar 471	. . . . 5 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ ¬ 𝑥 ∈ dom (𝐹 ∖ I )) → (𝐹‘𝑥) = 𝑥)
53		fveq2 6433	. . . . . 6 ⊢ ((𝐹‘𝑥) = 𝑥 → (𝐹‘(𝐹‘𝑥)) = (𝐹‘𝑥))
54		id 22	. . . . . 6 ⊢ ((𝐹‘𝑥) = 𝑥 → (𝐹‘𝑥) = 𝑥)
55	53, 54	eqtrd 2861	. . . . 5 ⊢ ((𝐹‘𝑥) = 𝑥 → (𝐹‘(𝐹‘𝑥)) = 𝑥)
56	52, 55	syl 17	. . . 4 ⊢ (((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) ∧ ¬ 𝑥 ∈ dom (𝐹 ∖ I )) → (𝐹‘(𝐹‘𝑥)) = 𝑥)
57	47, 56	pm2.61dan 847	. . 3 ⊢ ((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) → (𝐹‘(𝐹‘𝑥)) = 𝑥)
58		fvco2 6520	. . . 4 ⊢ ((𝐹 Fn 𝐷 ∧ 𝑥 ∈ 𝐷) → ((𝐹 ∘ 𝐹)‘𝑥) = (𝐹‘(𝐹‘𝑥)))
59	48, 58	sylan 575	. . 3 ⊢ ((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) → ((𝐹 ∘ 𝐹)‘𝑥) = (𝐹‘(𝐹‘𝑥)))
60		fvresi 6691	. . . 4 ⊢ (𝑥 ∈ 𝐷 → (( I ↾ 𝐷)‘𝑥) = 𝑥)
61	60	adantl 475	. . 3 ⊢ ((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) → (( I ↾ 𝐷)‘𝑥) = 𝑥)
62	57, 59, 61	3eqtr4d 2871	. 2 ⊢ ((𝐹 ∈ 𝑅 ∧ 𝑥 ∈ 𝐷) → ((𝐹 ∘ 𝐹)‘𝑥) = (( I ↾ 𝐷)‘𝑥))
63	14, 16, 62	eqfnfvd 6563	1 ⊢ (𝐹 ∈ 𝑅 → (𝐹 ∘ 𝐹) = ( I ↾ 𝐷))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 198   ∧ wa 386   ∧ w3a 1111   = wceq 1656   ∈ wcel 2164   ≠ wne 2999  Vcvv 3414   ∖ cdif 3795   ⊆ wss 3798  ifcif 4306  {csn 4397  ∪ cuni 4658   class class class wbr 4873   I cid 5249  dom cdm 5342  ran crn 5343   ↾ cres 5344   ∘ ccom 5346  suc csuc 5965   Fn wfn 6118  ⟶wf 6119  ‘cfv 6123  ωcom 7326  1_oc1o 7819  2_oc2o 7820   ≈ cen 8219  pmTrspcpmtr 18211

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1894  ax-4 1908  ax-5 2009  ax-6 2075  ax-7 2112  ax-8 2166  ax-9 2173  ax-10 2192  ax-11 2207  ax-12 2220  ax-13 2389  ax-ext 2803  ax-rep 4994  ax-sep 5005  ax-nul 5013  ax-pow 5065  ax-pr 5127  ax-un 7209

This theorem depends on definitions:  df-bi 199  df-an 387  df-or 879  df-3or 1112  df-3an 1113  df-tru 1660  df-ex 1879  df-nf 1883  df-sb 2068  df-mo 2605  df-eu 2640  df-clab 2812  df-cleq 2818  df-clel 2821  df-nfc 2958  df-ne 3000  df-ral 3122  df-rex 3123  df-reu 3124  df-rab 3126  df-v 3416  df-sbc 3663  df-csb 3758  df-dif 3801  df-un 3803  df-in 3805  df-ss 3812  df-pss 3814  df-nul 4145  df-if 4307  df-pw 4380  df-sn 4398  df-pr 4400  df-tp 4402  df-op 4404  df-uni 4659  df-iun 4742  df-br 4874  df-opab 4936  df-mpt 4953  df-tr 4976  df-id 5250  df-eprel 5255  df-po 5263  df-so 5264  df-fr 5301  df-we 5303  df-xp 5348  df-rel 5349  df-cnv 5350  df-co 5351  df-dm 5352  df-rn 5353  df-res 5354  df-ima 5355  df-ord 5966  df-on 5967  df-lim 5968  df-suc 5969  df-iota 6086  df-fun 6125  df-fn 6126  df-f 6127  df-f1 6128  df-fo 6129  df-f1o 6130  df-fv 6131  df-om 7327  df-1o 7826  df-2o 7827  df-er 8009  df-en 8223  df-dom 8224  df-sdom 8225  df-fin 8226  df-pmtr 18212

This theorem is referenced by:  pmtrff1o  18233  pmtrfcnv  18234  symggen  18240  psgnunilem1  18263