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Theorem pwfi 4545
Description: The power set of a finite set is finite and vice-versa. Theorem 38 of [Suppes] p. 104 and its converse, Theorem 40 of [Suppes] p. 105.
Assertion
Ref Expression
pwfi |- (E.n e. om A ~~ n <-> E.n e. om P~A ~~ n)
Distinct variable group:   A,n

Proof of Theorem pwfi
StepHypRef Expression
1 breq2 2613 . . . 4 |- (n = m -> (A ~~ n <-> A ~~ m))
21cbvrexv 1792 . . 3 |- (E.n e. om A ~~ n <-> E.m e. om A ~~ m)
3 visset 1804 . . . . . . . 8 |- m e. V
43pwen 4483 . . . . . . 7 |- (A ~~ m -> P~A ~~ P~m)
53pwex 2735 . . . . . . . 8 |- P~m e. V
6 enen1 4457 . . . . . . . 8 |- ((P~m e. V /\ P~A ~~ P~m) -> (P~A ~~ n <-> P~m ~~ n))
75, 6mpan 693 . . . . . . 7 |- (P~A ~~ P~m -> (P~A ~~ n <-> P~m ~~ n))
84, 7syl 10 . . . . . 6 |- (A ~~ m -> (P~A ~~ n <-> P~m ~~ n))
98rexbidv 1656 . . . . 5 |- (A ~~ m -> (E.n e. om P~A ~~ n <-> E.n e. om P~m ~~ n))
10 pweq 2393 . . . . . . . 8 |- (m = (/) -> P~m = P~(/))
1110breq1d 2619 . . . . . . 7 |- (m = (/) -> (P~m ~~ n <-> P~(/) ~~ n))
1211rexbidv 1656 . . . . . 6 |- (m = (/) -> (E.n e. om P~m ~~ n <-> E.n e. om P~(/) ~~ n))
13 pweq 2393 . . . . . . . 8 |- (m = k -> P~m = P~k)
1413breq1d 2619 . . . . . . 7 |- (m = k -> (P~m ~~ n <-> P~k ~~ n))
1514rexbidv 1656 . . . . . 6 |- (m = k -> (E.n e. om P~m ~~ n <-> E.n e. om P~k ~~ n))
16 df-suc 2944 . . . . . . . . . 10 |- suc k = (k u. {k})
1716eqeq2i 1477 . . . . . . . . 9 |- (m = suc k <-> m = (k u. {k}))
18 pweq 2393 . . . . . . . . 9 |- (m = (k u. {k}) -> P~m = P~(k u. {k}))
1917, 18sylbi 199 . . . . . . . 8 |- (m = suc k -> P~m = P~(k u. {k}))
2019breq1d 2619 . . . . . . 7 |- (m = suc k -> (P~m ~~ n <-> P~(k u. {k}) ~~ n))
2120rexbidv 1656 . . . . . 6 |- (m = suc k -> (E.n e. om P~m ~~ n <-> E.n e. om P~(k u. {k}) ~~ n))
22 1onn 4237 . . . . . . 7 |- 1o e. om
23 pw0 2459 . . . . . . . . 9 |- P~(/) = {(/)}
24 df1o2 4124 . . . . . . . . 9 |- 1o = {(/)}
2523, 24eqtr4 1490 . . . . . . . 8 |- P~(/) = 1o
2622elisseti 1809 . . . . . . . . 9 |- 1o e. V
2726enref 4372 . . . . . . . 8 |- 1o ~~ 1o
2825, 27eqbrtr 2624 . . . . . . 7 |- P~(/) ~~ 1o
29 breq2 2613 . . . . . . . 8 |- (n = 1o -> (P~(/) ~~ n <-> P~(/) ~~ 1o))
3029rcla4ev 1868 . . . . . . 7 |- ((1o e. om /\ P~(/) ~~ 1o) -> E.n e. om P~(/) ~~ n)
3122, 28, 30mp2an 695 . . . . . 6 |- E.n e. om P~(/) ~~ n
32 eqid 1468 . . . . . . . 8 |- {<.c, y>. | (c e. P~k /\ y = (c u. {k}))} = {<.c, y>. | (c e. P~k /\ y = (c u. {k}))}
3332pwfilem 4544 . . . . . . 7 |- (E.n e. om P~k ~~ n -> E.n e. om P~(k u. {k}) ~~ n)
3433a1i 8 . . . . . 6 |- (k e. om -> (E.n e. om P~k ~~ n -> E.n e. om P~(k u. {k}) ~~ n))
3512, 15, 21, 31, 34finds1 3149 . . . . 5 |- (m e. om -> E.n e. om P~m ~~ n)
369, 35syl5cbir 211 . . . 4 |- (m e. om -> (A ~~ m -> E.n e. om P~A ~~ n))
3736r19.23aiv 1735 . . 3 |- (E.m e. om A ~~ m -> E.n e. om P~A ~~ n)
382, 37sylbi 199 . 2 |- (E.n e. om A ~~ n -> E.n e. om P~A ~~ n)
39 relen 4354 . . . . . . . . 9 |- Rel ~~
4039brrelexi 3198 . . . . . . . 8 |- (P~A ~~ n -> P~A e. V)
41 pwexb 2898 . . . . . . . 8 |- (A e. V <-> P~A e. V)
4240, 41sylibr 200 . . . . . . 7 |- (P~A ~~ n -> A e. V)
43 canth2g 4466 . . . . . . 7 |- (A e. V -> A ~< P~A)
4442, 43syl 10 . . . . . 6 |- (P~A ~~ n -> A ~< P~A)
4544adantl 388 . . . . 5 |- ((n e. om /\ P~A ~~ n) -> A ~< P~A)
4645r19.23aiva 1736 . . . 4 |- (E.n e. om P~A ~~ n -> A ~< P~A)
47 sdomdom 4367 . . . 4 |- (A ~< P~A -> A ~<_ P~A)
4846, 47syl 10 . . 3 |- (E.n e. om P~A ~~ n -> A ~<_ P~A)
49 domfi 4516 . . 3 |- ((E.n e. om P~A ~~ n /\ A ~<_ P~A) -> E.n e. om A ~~ n)
5048, 49mpdan 702 . 2 |- (E.n e. om P~A ~~ n -> E.n e. om A ~~ n)
5138, 50impbi 157 1 |- (E.n e. om A ~~ n <-> E.n e. om P~A ~~ n)
Colors of variables: wff set class
Syntax hints:   -> wi 3   <-> wb 146   /\ wa 223   = wceq 953   e. wcel 955  E.wrex 1638  Vcvv 1802   u. cun 2035  (/)c0 2270  P~cpw 2391  {csn 2399   class class class wbr 2609  {copab 2656  suc csuc 2940  omcom 3121  1oc1o 4112   ~~ cen 4348   ~<_ cdom 4349   ~< csdm 4350
This theorem is referenced by:  dominf 4876
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-7 959  ax-gen 960  ax-8 961  ax-9 962  ax-10 963  ax-11 964  ax-12 965  ax-13 966  ax-14 967  ax-17 968  ax-4 970  ax-5o 972  ax-6o 975  ax-9o 1119  ax-10o 1136  ax-16 1206  ax-11o 1213  ax-ext 1452  ax-rep 2683  ax-sep 2693  ax-nul 2700  ax-pow 2732  ax-pr 2769  ax-un 2857
This theorem depends on definitions:  df-bi 147  df-or 224  df-an 225  df-3or 774  df-3an 775  df-ex 978  df-sb 1168  df-eu 1375  df-mo 1376  df-clab 1457  df-cleq 1462  df-clel 1465  df-ne 1579  df-ral 1641  df-rex 1642  df-reu 1643  df-rab 1644  df-v 1803  df-sbc 1932  df-csb 1992  df-dif 2039  df-un 2040  df-in 2041  df-ss 2043  df-pss 2045  df-nul 2271  df-if 2352  df-pw 2392  df-sn 2402  df-pr 2403  df-tp 2405  df-op 2406  df-uni 2494  df-int 2524  df-iun 2558  df-br 2610  df-opab 2657  df-tr 2671  df-eprel 2821  df-id 2824  df-po 2831  df-so 2841  df-fr 2907  df-we 2924  df-ord 2941  df-on 2942  df-lim 2943  df-suc 2944  df-om 3122  df-xp 3174  df-rel 3175  df-cnv 3176  df-co 3177  df-dm 3178  df-rn 3179  df-res 3180  df-ima 3181  df-fun 3182  df-fn 3183  df-f 3184  df-f1 3185  df-fo 3186  df-f1o 3187  df-fv 3188  df-rdg 3917  df-opr 3950  df-oprab 3951  df-1o 4117  df-2o 4118  df-oadd 4119  df-er 4245  df-map 4308  df-en 4351  df-dom 4352  df-sdom 4353
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