Theorem map1 6906

Description: Set exponentiation: ordinal 1 to any set is equinumerous to ordinal 1. Exercise 4.42(b) of [Mendelson] p. 255. (Contributed by NM, 17-Dec-2003.)

Assertion

Ref	Expression
map1	|- ( A e. V -> ( 1o ^m A ) ~~ 1o )

Proof of Theorem map1

Dummy variables x y are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		fnmap 6744	. . 3 |- ^m Fn ( _V X. _V )
2		1oex 6512	. . 3 |- 1o e. _V
3		elex 2783	. . 3 |- ( A e. V -> A e. _V )
4		fnovex 5979	. . 3 |- ( ( ^m Fn ( _V X. _V ) /\ 1o e. _V /\ A e. _V ) -> ( 1o ^m A ) e. _V )
5	1, 2, 3, 4	mp3an12i 1354	. 2 |- ( A e. V -> ( 1o ^m A ) e. _V )
6	2	a1i 9	. 2 |- ( A e. V -> 1o e. _V )
7		0ex 4172	. . 3 |- (/) e. _V
8	7	2a1i 27	. 2 |- ( A e. V -> ( x e. ( 1o ^m A ) -> (/) e. _V ) )
9		p0ex 4233	. . . 4 |- { (/) } e. _V
10		xpexg 4790	. . . 4 |- ( ( A e. V /\ { (/) } e. _V ) -> ( A X. { (/) } ) e. _V )
11	9, 10	mpan2 425	. . 3 |- ( A e. V -> ( A X. { (/) } ) e. _V )
12	11	a1d 22	. 2 |- ( A e. V -> ( y e. 1o -> ( A X. { (/) } ) e. _V ) )
13		el1o 6525	. . . . 5 |- ( y e. 1o <-> y = (/) )
14	13	a1i 9	. . . 4 |- ( A e. V -> ( y e. 1o <-> y = (/) ) )
15		df1o2 6517	. . . . . . . 8 |- 1o = { (/) }
16	15	oveq1i 5956	. . . . . . 7 |- ( 1o ^m A ) = ( { (/) } ^m A )
17	16	eleq2i 2272	. . . . . 6 |- ( x e. ( 1o ^m A ) <-> x e. ( { (/) } ^m A ) )
18		elmapg 6750	. . . . . . 7 |- ( ( { (/) } e. _V /\ A e. V ) -> ( x e. ( { (/) } ^m A ) <-> x : A --> { (/) } ) )
19	9, 18	mpan 424	. . . . . 6 |- ( A e. V -> ( x e. ( { (/) } ^m A ) <-> x : A --> { (/) } ) )
20	17, 19	bitrid 192	. . . . 5 |- ( A e. V -> ( x e. ( 1o ^m A ) <-> x : A --> { (/) } ) )
21	7	fconst2 5803	. . . . 5 |- ( x : A --> { (/) } <-> x = ( A X. { (/) } ) )
22	20, 21	bitr2di 197	. . . 4 |- ( A e. V -> ( x = ( A X. { (/) } ) <-> x e. ( 1o ^m A ) ) )
23	14, 22	anbi12d 473	. . 3 |- ( A e. V -> ( ( y e. 1o /\ x = ( A X. { (/) } ) ) <-> ( y = (/) /\ x e. ( 1o ^m A ) ) ) )
24		ancom 266	. . 3 |- ( ( y = (/) /\ x e. ( 1o ^m A ) ) <-> ( x e. ( 1o ^m A ) /\ y = (/) ) )
25	23, 24	bitr2di 197	. 2 |- ( A e. V -> ( ( x e. ( 1o ^m A ) /\ y = (/) ) <-> ( y e. 1o /\ x = ( A X. { (/) } ) ) ) )
26	5, 6, 8, 12, 25	en2d 6861	1 |- ( A e. V -> ( 1o ^m A ) ~~ 1o )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1373   e. wcel 2176   _Vcvv 2772   (/)c0 3460   {csn 3633   class class class wbr 4045   X. cxp 4674   Fn wfn 5267   -->wf 5268  (class class class)co 5946   1oc1o 6497   ^m cmap 6737   ~~ cen 6827

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 615  ax-in2 616  ax-io 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-13 2178  ax-14 2179  ax-ext 2187  ax-sep 4163  ax-nul 4171  ax-pow 4219  ax-pr 4254  ax-un 4481  ax-setind 4586

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-fal 1379  df-nf 1484  df-sb 1786  df-eu 2057  df-mo 2058  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ne 2377  df-ral 2489  df-rex 2490  df-rab 2493  df-v 2774  df-sbc 2999  df-csb 3094  df-dif 3168  df-un 3170  df-in 3172  df-ss 3179  df-nul 3461  df-pw 3618  df-sn 3639  df-pr 3640  df-op 3642  df-uni 3851  df-iun 3929  df-br 4046  df-opab 4107  df-mpt 4108  df-tr 4144  df-id 4341  df-iord 4414  df-on 4416  df-suc 4419  df-xp 4682  df-rel 4683  df-cnv 4684  df-co 4685  df-dm 4686  df-rn 4687  df-res 4688  df-ima 4689  df-iota 5233  df-fun 5274  df-fn 5275  df-f 5276  df-f1 5277  df-fo 5278  df-f1o 5279  df-fv 5280  df-ov 5949  df-oprab 5950  df-mpo 5951  df-1st 6228  df-2nd 6229  df-1o 6504  df-map 6739  df-en 6830

This theorem is referenced by: (None)