Theorem gicsubgen 19337

Description: A less trivial example of a group invariant: cardinality of the subgroup lattice. (Contributed by Stefan O'Rear, 25-Jan-2015.)

Assertion

Ref	Expression
gicsubgen	⊢ (𝑅 ≃𝑔 𝑆 → (SubGrp‘𝑅) ≈ (SubGrp‘𝑆))

Proof of Theorem gicsubgen

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

Step	Hyp	Ref	Expression
1		brgic 19328	. . 3 ⊢ (𝑅 ≃𝑔 𝑆 ↔ (𝑅 GrpIso 𝑆) ≠ ∅)
2		n0 4308	. . 3 ⊢ ((𝑅 GrpIso 𝑆) ≠ ∅ ↔ ∃𝑎 𝑎 ∈ (𝑅 GrpIso 𝑆))
3	1, 2	bitri 278	. 2 ⊢ (𝑅 ≃𝑔 𝑆 ↔ ∃𝑎 𝑎 ∈ (𝑅 GrpIso 𝑆))
4		fvexd 6886	. . . 4 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → (SubGrp‘𝑅) ∈ V)
5		fvexd 6886	. . . 4 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → (SubGrp‘𝑆) ∈ V)
6		vex 3461	. . . . . 6 ⊢ 𝑎 ∈ V
7	6	imaex 7899	. . . . 5 ⊢ (𝑎 “ 𝑏) ∈ V
8	7	2a1i 12	. . . 4 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → (𝑏 ∈ (SubGrp‘𝑅) → (𝑎 “ 𝑏) ∈ V))
9	6	cnvex 7910	. . . . . 6 ⊢ ◡𝑎 ∈ V
10	9	imaex 7899	. . . . 5 ⊢ (◡𝑎 “ 𝑐) ∈ V
11	10	2a1i 12	. . . 4 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → (𝑐 ∈ (SubGrp‘𝑆) → (◡𝑎 “ 𝑐) ∈ V))
12		gimghm 19322	. . . . . . . . 9 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → 𝑎 ∈ (𝑅 GrpHom 𝑆))
13		ghmima 19295	. . . . . . . . 9 ⊢ ((𝑎 ∈ (𝑅 GrpHom 𝑆) ∧ 𝑏 ∈ (SubGrp‘𝑅)) → (𝑎 “ 𝑏) ∈ (SubGrp‘𝑆))
14	12, 13	sylan 591	. . . . . . . 8 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑏 ∈ (SubGrp‘𝑅)) → (𝑎 “ 𝑏) ∈ (SubGrp‘𝑆))
15		eqid 2765	. . . . . . . . . . . 12 ⊢ (Base‘𝑅) = (Base‘𝑅)
16		eqid 2765	. . . . . . . . . . . 12 ⊢ (Base‘𝑆) = (Base‘𝑆)
17	15, 16	gimf1o 19321	. . . . . . . . . . 11 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → 𝑎:(Base‘𝑅)–1-1-onto→(Base‘𝑆))
18		f1of1 6809	. . . . . . . . . . 11 ⊢ (𝑎:(Base‘𝑅)–1-1-onto→(Base‘𝑆) → 𝑎:(Base‘𝑅)–1-1→(Base‘𝑆))
19	17, 18	syl 18	. . . . . . . . . 10 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → 𝑎:(Base‘𝑅)–1-1→(Base‘𝑆))
20	15	subgss 19181	. . . . . . . . . 10 ⊢ (𝑏 ∈ (SubGrp‘𝑅) → 𝑏 ⊆ (Base‘𝑅))
21		f1imacnv 6827	. . . . . . . . . 10 ⊢ ((𝑎:(Base‘𝑅)–1-1→(Base‘𝑆) ∧ 𝑏 ⊆ (Base‘𝑅)) → (◡𝑎 “ (𝑎 “ 𝑏)) = 𝑏)
22	19, 20, 21	syl2an 607	. . . . . . . . 9 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑏 ∈ (SubGrp‘𝑅)) → (◡𝑎 “ (𝑎 “ 𝑏)) = 𝑏)
23	22	eqcomd 2771	. . . . . . . 8 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑏 ∈ (SubGrp‘𝑅)) → 𝑏 = (◡𝑎 “ (𝑎 “ 𝑏)))
24	14, 23	jca 520	. . . . . . 7 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑏 ∈ (SubGrp‘𝑅)) → ((𝑎 “ 𝑏) ∈ (SubGrp‘𝑆) ∧ 𝑏 = (◡𝑎 “ (𝑎 “ 𝑏))))
25		eleq1 2853	. . . . . . . 8 ⊢ (𝑐 = (𝑎 “ 𝑏) → (𝑐 ∈ (SubGrp‘𝑆) ↔ (𝑎 “ 𝑏) ∈ (SubGrp‘𝑆)))
26		imaeq2 6048	. . . . . . . . 9 ⊢ (𝑐 = (𝑎 “ 𝑏) → (◡𝑎 “ 𝑐) = (◡𝑎 “ (𝑎 “ 𝑏)))
27	26	eqeq2d 2776	. . . . . . . 8 ⊢ (𝑐 = (𝑎 “ 𝑏) → (𝑏 = (◡𝑎 “ 𝑐) ↔ 𝑏 = (◡𝑎 “ (𝑎 “ 𝑏))))
28	25, 27	anbi12d 643	. . . . . . 7 ⊢ (𝑐 = (𝑎 “ 𝑏) → ((𝑐 ∈ (SubGrp‘𝑆) ∧ 𝑏 = (◡𝑎 “ 𝑐)) ↔ ((𝑎 “ 𝑏) ∈ (SubGrp‘𝑆) ∧ 𝑏 = (◡𝑎 “ (𝑎 “ 𝑏)))))
29	24, 28	syl5ibrcom 250	. . . . . 6 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑏 ∈ (SubGrp‘𝑅)) → (𝑐 = (𝑎 “ 𝑏) → (𝑐 ∈ (SubGrp‘𝑆) ∧ 𝑏 = (◡𝑎 “ 𝑐))))
30	29	impr 459	. . . . 5 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ (𝑏 ∈ (SubGrp‘𝑅) ∧ 𝑐 = (𝑎 “ 𝑏))) → (𝑐 ∈ (SubGrp‘𝑆) ∧ 𝑏 = (◡𝑎 “ 𝑐)))
31		ghmpreima 19296	. . . . . . . . 9 ⊢ ((𝑎 ∈ (𝑅 GrpHom 𝑆) ∧ 𝑐 ∈ (SubGrp‘𝑆)) → (◡𝑎 “ 𝑐) ∈ (SubGrp‘𝑅))
32	12, 31	sylan 591	. . . . . . . 8 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑐 ∈ (SubGrp‘𝑆)) → (◡𝑎 “ 𝑐) ∈ (SubGrp‘𝑅))
33		f1ofo 6818	. . . . . . . . . . 11 ⊢ (𝑎:(Base‘𝑅)–1-1-onto→(Base‘𝑆) → 𝑎:(Base‘𝑅)–onto→(Base‘𝑆))
34	17, 33	syl 18	. . . . . . . . . 10 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → 𝑎:(Base‘𝑅)–onto→(Base‘𝑆))
35	16	subgss 19181	. . . . . . . . . 10 ⊢ (𝑐 ∈ (SubGrp‘𝑆) → 𝑐 ⊆ (Base‘𝑆))
36		foimacnv 6828	. . . . . . . . . 10 ⊢ ((𝑎:(Base‘𝑅)–onto→(Base‘𝑆) ∧ 𝑐 ⊆ (Base‘𝑆)) → (𝑎 “ (◡𝑎 “ 𝑐)) = 𝑐)
37	34, 35, 36	syl2an 607	. . . . . . . . 9 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑐 ∈ (SubGrp‘𝑆)) → (𝑎 “ (◡𝑎 “ 𝑐)) = 𝑐)
38	37	eqcomd 2771	. . . . . . . 8 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑐 ∈ (SubGrp‘𝑆)) → 𝑐 = (𝑎 “ (◡𝑎 “ 𝑐)))
39	32, 38	jca 520	. . . . . . 7 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑐 ∈ (SubGrp‘𝑆)) → ((◡𝑎 “ 𝑐) ∈ (SubGrp‘𝑅) ∧ 𝑐 = (𝑎 “ (◡𝑎 “ 𝑐))))
40		eleq1 2853	. . . . . . . 8 ⊢ (𝑏 = (◡𝑎 “ 𝑐) → (𝑏 ∈ (SubGrp‘𝑅) ↔ (◡𝑎 “ 𝑐) ∈ (SubGrp‘𝑅)))
41		imaeq2 6048	. . . . . . . . 9 ⊢ (𝑏 = (◡𝑎 “ 𝑐) → (𝑎 “ 𝑏) = (𝑎 “ (◡𝑎 “ 𝑐)))
42	41	eqeq2d 2776	. . . . . . . 8 ⊢ (𝑏 = (◡𝑎 “ 𝑐) → (𝑐 = (𝑎 “ 𝑏) ↔ 𝑐 = (𝑎 “ (◡𝑎 “ 𝑐))))
43	40, 42	anbi12d 643	. . . . . . 7 ⊢ (𝑏 = (◡𝑎 “ 𝑐) → ((𝑏 ∈ (SubGrp‘𝑅) ∧ 𝑐 = (𝑎 “ 𝑏)) ↔ ((◡𝑎 “ 𝑐) ∈ (SubGrp‘𝑅) ∧ 𝑐 = (𝑎 “ (◡𝑎 “ 𝑐)))))
44	39, 43	syl5ibrcom 250	. . . . . 6 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ 𝑐 ∈ (SubGrp‘𝑆)) → (𝑏 = (◡𝑎 “ 𝑐) → (𝑏 ∈ (SubGrp‘𝑅) ∧ 𝑐 = (𝑎 “ 𝑏))))
45	44	impr 459	. . . . 5 ⊢ ((𝑎 ∈ (𝑅 GrpIso 𝑆) ∧ (𝑐 ∈ (SubGrp‘𝑆) ∧ 𝑏 = (◡𝑎 “ 𝑐))) → (𝑏 ∈ (SubGrp‘𝑅) ∧ 𝑐 = (𝑎 “ 𝑏)))
46	30, 45	impbida 812	. . . 4 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → ((𝑏 ∈ (SubGrp‘𝑅) ∧ 𝑐 = (𝑎 “ 𝑏)) ↔ (𝑐 ∈ (SubGrp‘𝑆) ∧ 𝑏 = (◡𝑎 “ 𝑐))))
47	4, 5, 8, 11, 46	en2d 8973	. . 3 ⊢ (𝑎 ∈ (𝑅 GrpIso 𝑆) → (SubGrp‘𝑅) ≈ (SubGrp‘𝑆))
48	47	exlimiv 1953	. 2 ⊢ (∃𝑎 𝑎 ∈ (𝑅 GrpIso 𝑆) → (SubGrp‘𝑅) ≈ (SubGrp‘𝑆))
49	3, 48	sylbi 220	1 ⊢ (𝑅 ≃𝑔 𝑆 → (SubGrp‘𝑅) ≈ (SubGrp‘𝑆))

Syntax hints:   → wi 4   ∧ wa 400   = wceq 1563  ∃wex 1802   ∈ wcel 2145   ≠ wne 2960  Vcvv 3457   ⊆ wss 3907  ∅c0 4288   class class class wbr 5104  ^◡ccnv 5650   “ cima 5654  –1-1→wf1 6522  –onto→wfo 6523  –1-1-onto→wf1o 6524  ‘cfv 6525  (class class class)co 7400   ≈ cen 8928  Basecbs 17257  SubGrpcsubg 19174   GrpHom cghm 19271   GrpIso cgim 19315   ≃_𝑔 cgic 19316

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1818  ax-4 1832  ax-5 1933  ax-6 1990  ax-7 2031  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2737  ax-sep 5250  ax-nul 5260  ax-pow 5326  ax-pr 5394  ax-un 7722  ax-cnex 11144  ax-resscn 11145  ax-1cn 11146  ax-icn 11147  ax-addcl 11148  ax-addrcl 11149  ax-mulcl 11150  ax-mulrcl 11151  ax-mulcom 11152  ax-addass 11153  ax-mulass 11154  ax-distr 11155  ax-i2m1 11156  ax-1ne0 11157  ax-1rid 11158  ax-rnegex 11159  ax-rrecex 11160  ax-cnre 11161  ax-pre-lttri 11162  ax-pre-lttrn 11163  ax-pre-ltadd 11164  ax-pre-mulgt0 11165

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3or 1102  df-3an 1103  df-tru 1566  df-fal 1576  df-ex 1803  df-nf 1807  df-sb 2094  df-mo 2569  df-eu 2599  df-clab 2744  df-cleq 2757  df-clel 2840  df-nfc 2914  df-ne 2961  df-nel 3065  df-ral 3080  df-rex 3090  df-rmo 3370  df-reu 3371  df-rab 3418  df-v 3459  df-sbc 3748  df-csb 3856  df-dif 3910  df-un 3912  df-in 3914  df-ss 3924  df-pss 3927  df-nul 4289  df-if 4484  df-pw 4560  df-sn 4586  df-pr 4588  df-op 4592  df-uni 4868  df-iun 4953  df-br 5105  df-opab 5167  df-mpt 5186  df-tr 5212  df-id 5546  df-eprel 5551  df-po 5559  df-so 5560  df-fr 5604  df-we 5606  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-rn 5662  df-res 5663  df-ima 5664  df-pred 6291  df-ord 6352  df-on 6353  df-lim 6354  df-suc 6355  df-iota 6481  df-fun 6527  df-fn 6528  df-f 6529  df-f1 6530  df-fo 6531  df-f1o 6532  df-fv 6533  df-riota 7357  df-ov 7403  df-oprab 7404  df-mpo 7405  df-om 7851  df-1st 7974  df-2nd 7975  df-frecs 8266  df-wrecs 8297  df-recs 8346  df-rdg 8385  df-1o 8441  df-er 8682  df-map 8814  df-en 8932  df-dom 8933  df-sdom 8934  df-pnf 11233  df-mnf 11234  df-xr 11235  df-ltxr 11236  df-le 11237  df-sub 11431  df-neg 11432  df-nn 12222  df-2 12291  df-sets 17212  df-slot 17230  df-ndx 17242  df-base 17258  df-ress 17279  df-plusg 17311  df-0g 17482  df-mgm 18686  df-sgrp 18765  df-mnd 18781  df-grp 18991  df-minusg 18992  df-subg 19177  df-ghm 19272  df-gim 19317  df-gic 19318

This theorem is referenced by: (None)