Theorem f1finf1o 8187

Description: Any injection from one finite set to another of equal size must be a bijection. (Contributed by Jeff Madsen, 5-Jun-2010.) (Revised by Mario Carneiro, 27-Feb-2014.)

Assertion

Ref	Expression
f1finf1o	|- ( ( A ~~ B /\ B e. Fin ) -> ( F : A -1-1-> B <-> F : A -1-1-onto-> B ) )

Proof of Theorem f1finf1o

Step	Hyp	Ref	Expression
1		simpr 477	. . . 4 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> F : A -1-1-> B )
2		f1f 6101	. . . . . . 7 |- ( F : A -1-1-> B -> F : A --> B )
3	2	adantl 482	. . . . . 6 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> F : A --> B )
4		ffn 6045	. . . . . 6 |- ( F : A --> B -> F Fn A )
5	3, 4	syl 17	. . . . 5 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> F Fn A )
6		simpll 790	. . . . . 6 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> A ~~ B )
7		frn 6053	. . . . . . . . . 10 |- ( F : A --> B -> ran F C_ B )
8	3, 7	syl 17	. . . . . . . . 9 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ran F C_ B )
9		df-pss 3590	. . . . . . . . . 10 |- ( ran F C. B <-> ( ran F C_ B /\ ran F =/= B ) )
10	9	baib 944	. . . . . . . . 9 |- ( ran F C_ B -> ( ran F C. B <-> ran F =/= B ) )
11	8, 10	syl 17	. . . . . . . 8 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ( ran F C. B <-> ran F =/= B ) )
12		simplr 792	. . . . . . . . . . . . 13 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> B e. Fin )
13		relen 7960	. . . . . . . . . . . . . . 15 |- Rel ~~
14	13	brrelexi 5158	. . . . . . . . . . . . . 14 |- ( A ~~ B -> A e. _V )
15	6, 14	syl 17	. . . . . . . . . . . . 13 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> A e. _V )
16	12, 15	elmapd 7871	. . . . . . . . . . . 12 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ( F e. ( B ^m A ) <-> F : A --> B ) )
17	3, 16	mpbird 247	. . . . . . . . . . 11 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> F e. ( B ^m A ) )
18		f1f1orn 6148	. . . . . . . . . . . 12 |- ( F : A -1-1-> B -> F : A -1-1-onto-> ran F )
19	18	adantl 482	. . . . . . . . . . 11 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> F : A -1-1-onto-> ran F )
20		f1oen3g 7971	. . . . . . . . . . 11 |- ( ( F e. ( B ^m A ) /\ F : A -1-1-onto-> ran F ) -> A ~~ ran F )
21	17, 19, 20	syl2anc 693	. . . . . . . . . 10 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> A ~~ ran F )
22		php3 8146	. . . . . . . . . . . 12 |- ( ( B e. Fin /\ ran F C. B ) -> ran F ~< B )
23	22	ex 450	. . . . . . . . . . 11 |- ( B e. Fin -> ( ran F C. B -> ran F ~< B ) )
24	12, 23	syl 17	. . . . . . . . . 10 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ( ran F C. B -> ran F ~< B ) )
25		ensdomtr 8096	. . . . . . . . . 10 |- ( ( A ~~ ran F /\ ran F ~< B ) -> A ~< B )
26	21, 24, 25	syl6an 568	. . . . . . . . 9 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ( ran F C. B -> A ~< B ) )
27		sdomnen 7984	. . . . . . . . 9 |- ( A ~< B -> -. A ~~ B )
28	26, 27	syl6 35	. . . . . . . 8 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ( ran F C. B -> -. A ~~ B ) )
29	11, 28	sylbird 250	. . . . . . 7 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ( ran F =/= B -> -. A ~~ B ) )
30	29	necon4ad 2813	. . . . . 6 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ( A ~~ B -> ran F = B ) )
31	6, 30	mpd 15	. . . . 5 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> ran F = B )
32		df-fo 5894	. . . . 5 |- ( F : A -onto-> B <-> ( F Fn A /\ ran F = B ) )
33	5, 31, 32	sylanbrc 698	. . . 4 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> F : A -onto-> B )
34		df-f1o 5895	. . . 4 |- ( F : A -1-1-onto-> B <-> ( F : A -1-1-> B /\ F : A -onto-> B ) )
35	1, 33, 34	sylanbrc 698	. . 3 |- ( ( ( A ~~ B /\ B e. Fin ) /\ F : A -1-1-> B ) -> F : A -1-1-onto-> B )
36	35	ex 450	. 2 |- ( ( A ~~ B /\ B e. Fin ) -> ( F : A -1-1-> B -> F : A -1-1-onto-> B ) )
37		f1of1 6136	. 2 |- ( F : A -1-1-onto-> B -> F : A -1-1-> B )
38	36, 37	impbid1 215	1 |- ( ( A ~~ B /\ B e. Fin ) -> ( F : A -1-1-> B <-> F : A -1-1-onto-> B ) )

Syntax hints:   -. wn 3   -> wi 4   <-> wb 196   /\ wa 384   = wceq 1483   e. wcel 1990   =/= wne 2794   _Vcvv 3200   C_ wss 3574   C. wpss 3575   class class class wbr 4653   ran crn 5115   Fn wfn 5883   -->wf 5884   -1-1->wf1 5885   -onto->wfo 5886   -1-1-onto->wf1o 5887  (class class class)co 6650   ^m cmap 7857   ~~ cen 7952   ~< csdm 7954   Fincfn 7955

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-ral 2917  df-rex 2918  df-rab 2921  df-v 3202  df-sbc 3436  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-pss 3590  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-tp 4182  df-op 4184  df-uni 4437  df-br 4654  df-opab 4713  df-tr 4753  df-id 5024  df-eprel 5029  df-po 5035  df-so 5036  df-fr 5073  df-we 5075  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-ord 5726  df-on 5727  df-lim 5728  df-suc 5729  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-om 7066  df-er 7742  df-map 7859  df-en 7956  df-dom 7957  df-sdom 7958  df-fin 7959

This theorem is referenced by:  hashfac  13242  crth  15483  eulerthlem2  15487  fidomndrnglem  19306  mdetunilem8  20425  basellem4  24810  lgsqrlem4  25074  lgseisenlem2  25101