MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  marypha1 Structured version   Visualization version   Unicode version

Theorem marypha1 8340
Description: (Philip) Hall's marriage theorem, sufficiency: a finite relation contains an injection if there is no subset of its domain which would be forced to violate the pigeonhole principle. (Contributed by Stefan O'Rear, 20-Feb-2015.)
Hypotheses
Ref Expression
marypha1.a  |-  ( ph  ->  A  e.  Fin )
marypha1.b  |-  ( ph  ->  B  e.  Fin )
marypha1.c  |-  ( ph  ->  C  C_  ( A  X.  B ) )
marypha1.d  |-  ( (
ph  /\  d  C_  A )  ->  d  ~<_  ( C " d ) )
Assertion
Ref Expression
marypha1  |-  ( ph  ->  E. f  e.  ~P  C f : A -1-1-> B )
Distinct variable groups:    ph, d, f    A, d, f    C, d, f
Allowed substitution hints:    B( f, d)

Proof of Theorem marypha1
Dummy variables  b 
c are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 elpwi 4168 . . . . 5  |-  ( d  e.  ~P A  -> 
d  C_  A )
2 marypha1.d . . . . 5  |-  ( (
ph  /\  d  C_  A )  ->  d  ~<_  ( C " d ) )
31, 2sylan2 491 . . . 4  |-  ( (
ph  /\  d  e.  ~P A )  ->  d  ~<_  ( C " d ) )
43ralrimiva 2966 . . 3  |-  ( ph  ->  A. d  e.  ~P  A d  ~<_  ( C
" d ) )
5 marypha1.c . . . . 5  |-  ( ph  ->  C  C_  ( A  X.  B ) )
6 marypha1.a . . . . . . 7  |-  ( ph  ->  A  e.  Fin )
7 marypha1.b . . . . . . 7  |-  ( ph  ->  B  e.  Fin )
8 xpexg 6960 . . . . . . 7  |-  ( ( A  e.  Fin  /\  B  e.  Fin )  ->  ( A  X.  B
)  e.  _V )
96, 7, 8syl2anc 693 . . . . . 6  |-  ( ph  ->  ( A  X.  B
)  e.  _V )
10 elpw2g 4827 . . . . . 6  |-  ( ( A  X.  B )  e.  _V  ->  ( C  e.  ~P ( A  X.  B )  <->  C  C_  ( A  X.  B ) ) )
119, 10syl 17 . . . . 5  |-  ( ph  ->  ( C  e.  ~P ( A  X.  B
)  <->  C  C_  ( A  X.  B ) ) )
125, 11mpbird 247 . . . 4  |-  ( ph  ->  C  e.  ~P ( A  X.  B ) )
13 xpeq2 5129 . . . . . . . . 9  |-  ( b  =  B  ->  ( A  X.  b )  =  ( A  X.  B
) )
1413pweqd 4163 . . . . . . . 8  |-  ( b  =  B  ->  ~P ( A  X.  b
)  =  ~P ( A  X.  B ) )
1514raleqdv 3144 . . . . . . 7  |-  ( b  =  B  ->  ( A. c  e.  ~P  ( A  X.  b
) ( A. d  e.  ~P  A d  ~<_  ( c " d )  ->  E. f  e.  ~P  c f : A -1-1-> _V )  <->  A. c  e.  ~P  ( A  X.  B
) ( A. d  e.  ~P  A d  ~<_  ( c " d )  ->  E. f  e.  ~P  c f : A -1-1-> _V ) ) )
1615imbi2d 330 . . . . . 6  |-  ( b  =  B  ->  (
( A  e.  Fin  ->  A. c  e.  ~P  ( A  X.  b
) ( A. d  e.  ~P  A d  ~<_  ( c " d )  ->  E. f  e.  ~P  c f : A -1-1-> _V ) )  <->  ( A  e.  Fin  ->  A. c  e.  ~P  ( A  X.  B ) ( A. d  e.  ~P  A
d  ~<_  ( c "
d )  ->  E. f  e.  ~P  c f : A -1-1-> _V ) ) ) )
17 marypha1lem 8339 . . . . . . 7  |-  ( A  e.  Fin  ->  (
b  e.  Fin  ->  A. c  e.  ~P  ( A  X.  b ) ( A. d  e.  ~P  A d  ~<_  ( c
" d )  ->  E. f  e.  ~P  c f : A -1-1-> _V ) ) )
1817com12 32 . . . . . 6  |-  ( b  e.  Fin  ->  ( A  e.  Fin  ->  A. c  e.  ~P  ( A  X.  b ) ( A. d  e.  ~P  A
d  ~<_  ( c "
d )  ->  E. f  e.  ~P  c f : A -1-1-> _V ) ) )
1916, 18vtoclga 3272 . . . . 5  |-  ( B  e.  Fin  ->  ( A  e.  Fin  ->  A. c  e.  ~P  ( A  X.  B ) ( A. d  e.  ~P  A
d  ~<_  ( c "
d )  ->  E. f  e.  ~P  c f : A -1-1-> _V ) ) )
207, 6, 19sylc 65 . . . 4  |-  ( ph  ->  A. c  e.  ~P  ( A  X.  B
) ( A. d  e.  ~P  A d  ~<_  ( c " d )  ->  E. f  e.  ~P  c f : A -1-1-> _V ) )
21 imaeq1 5461 . . . . . . . 8  |-  ( c  =  C  ->  (
c " d )  =  ( C "
d ) )
2221breq2d 4665 . . . . . . 7  |-  ( c  =  C  ->  (
d  ~<_  ( c "
d )  <->  d  ~<_  ( C
" d ) ) )
2322ralbidv 2986 . . . . . 6  |-  ( c  =  C  ->  ( A. d  e.  ~P  A d  ~<_  ( c
" d )  <->  A. d  e.  ~P  A d  ~<_  ( C " d ) ) )
24 pweq 4161 . . . . . . 7  |-  ( c  =  C  ->  ~P c  =  ~P C
)
2524rexeqdv 3145 . . . . . 6  |-  ( c  =  C  ->  ( E. f  e.  ~P  c f : A -1-1-> _V  <->  E. f  e.  ~P  C
f : A -1-1-> _V ) )
2623, 25imbi12d 334 . . . . 5  |-  ( c  =  C  ->  (
( A. d  e. 
~P  A d  ~<_  ( c " d )  ->  E. f  e.  ~P  c f : A -1-1-> _V )  <->  ( A. d  e.  ~P  A d  ~<_  ( C " d )  ->  E. f  e.  ~P  C f : A -1-1-> _V ) ) )
2726rspcva 3307 . . . 4  |-  ( ( C  e.  ~P ( A  X.  B )  /\  A. c  e.  ~P  ( A  X.  B ) ( A. d  e.  ~P  A d  ~<_  ( c
" d )  ->  E. f  e.  ~P  c f : A -1-1-> _V ) )  ->  ( A. d  e.  ~P  A d  ~<_  ( C
" d )  ->  E. f  e.  ~P  C f : A -1-1-> _V ) )
2812, 20, 27syl2anc 693 . . 3  |-  ( ph  ->  ( A. d  e. 
~P  A d  ~<_  ( C " d )  ->  E. f  e.  ~P  C f : A -1-1-> _V ) )
294, 28mpd 15 . 2  |-  ( ph  ->  E. f  e.  ~P  C f : A -1-1-> _V )
30 elpwi 4168 . . . . . . 7  |-  ( f  e.  ~P C  -> 
f  C_  C )
3130, 5sylan9ssr 3617 . . . . . 6  |-  ( (
ph  /\  f  e.  ~P C )  ->  f  C_  ( A  X.  B
) )
32 rnss 5354 . . . . . 6  |-  ( f 
C_  ( A  X.  B )  ->  ran  f  C_  ran  ( A  X.  B ) )
3331, 32syl 17 . . . . 5  |-  ( (
ph  /\  f  e.  ~P C )  ->  ran  f  C_  ran  ( A  X.  B ) )
34 rnxpss 5566 . . . . 5  |-  ran  ( A  X.  B )  C_  B
3533, 34syl6ss 3615 . . . 4  |-  ( (
ph  /\  f  e.  ~P C )  ->  ran  f  C_  B )
36 f1ssr 6107 . . . . 5  |-  ( ( f : A -1-1-> _V  /\ 
ran  f  C_  B
)  ->  f : A -1-1-> B )
3736expcom 451 . . . 4  |-  ( ran  f  C_  B  ->  ( f : A -1-1-> _V  ->  f : A -1-1-> B
) )
3835, 37syl 17 . . 3  |-  ( (
ph  /\  f  e.  ~P C )  ->  (
f : A -1-1-> _V  ->  f : A -1-1-> B
) )
3938reximdva 3017 . 2  |-  ( ph  ->  ( E. f  e. 
~P  C f : A -1-1-> _V  ->  E. f  e.  ~P  C f : A -1-1-> B ) )
4029, 39mpd 15 1  |-  ( ph  ->  E. f  e.  ~P  C f : A -1-1-> B )
Colors of variables: wff setvar class
Syntax hints:    -> wi 4    <-> wb 196    /\ wa 384    = wceq 1483    e. wcel 1990   A.wral 2912   E.wrex 2913   _Vcvv 3200    C_ wss 3574   ~Pcpw 4158   class class class wbr 4653    X. cxp 5112   ran crn 5115   "cima 5117   -1-1->wf1 5885    ~<_ cdom 7953   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-om 7066  df-1o 7560  df-er 7742  df-en 7956  df-dom 7957  df-sdom 7958  df-fin 7959
This theorem is referenced by:  marypha2  8345
  Copyright terms: Public domain W3C validator