Theorem eldprd 18403

Description: A class A is an internal direct product iff it is the (group) sum of an infinite, but finitely supported cartesian product of subgroups (which mutually commute and have trivial intersections). (Contributed by Mario Carneiro, 25-Apr-2016.) (Revised by AV, 11-Jul-2019.)

Hypotheses

Ref	Expression
dprdval.0	|- .0. = ( 0g ` G )
dprdval.w	|- W = { h e. X_ i e. I ( S ` i ) | h finSupp .0. }

Assertion

Ref	Expression
eldprd	|- ( dom S = I -> ( A e. ( G DProd S ) <-> ( G dom DProd S /\ E. f e. W A = ( G gsumg f ) ) ) )

Distinct variable groups:   f, h, i   A, f   f, I, h, i   S, f, h, i   f, G, h, i

Allowed substitution hints:   A( h, i)   W( f, h, i)   .0. ( f, h, i)

Proof of Theorem eldprd

Step	Hyp	Ref	Expression
1		elfvdm 6220	. . . . 5 |- ( A e. ( DProd ` <. G , S >. ) -> <. G , S >. e. dom DProd )
2		df-ov 6653	. . . . 5 |- ( G DProd S ) = ( DProd ` <. G , S >. )
3	1, 2	eleq2s 2719	. . . 4 |- ( A e. ( G DProd S ) -> <. G , S >. e. dom DProd )
4		df-br 4654	. . . 4 |- ( G dom DProd S <-> <. G , S >. e. dom DProd )
5	3, 4	sylibr 224	. . 3 |- ( A e. ( G DProd S ) -> G dom DProd S )
6	5	pm4.71ri 665	. 2 |- ( A e. ( G DProd S ) <-> ( G dom DProd S /\ A e. ( G DProd S ) ) )
7		dprdval.0	. . . . . . 7 |- .0. = ( 0g ` G )
8		dprdval.w	. . . . . . 7 |- W = { h e. X_ i e. I ( S ` i ) | h finSupp .0. }
9	7, 8	dprdval 18402	. . . . . 6 |- ( ( G dom DProd S /\ dom S = I ) -> ( G DProd S ) = ran ( f e. W |-> ( G gsumg f ) ) )
10	9	eleq2d 2687	. . . . 5 |- ( ( G dom DProd S /\ dom S = I ) -> ( A e. ( G DProd S ) <-> A e. ran ( f e. W |-> ( G gsumg f ) ) ) )
11		eqid 2622	. . . . . 6 |- ( f e. W |-> ( G gsumg f ) ) = ( f e. W |-> ( G gsumg f ) )
12		ovex 6678	. . . . . 6 |- ( G gsumg f ) e. _V
13	11, 12	elrnmpti 5376	. . . . 5 |- ( A e. ran ( f e. W |-> ( G gsumg f ) ) <-> E. f e. W A = ( G gsumg f ) )
14	10, 13	syl6bb 276	. . . 4 |- ( ( G dom DProd S /\ dom S = I ) -> ( A e. ( G DProd S ) <-> E. f e. W A = ( G gsumg f ) ) )
15	14	ancoms 469	. . 3 |- ( ( dom S = I /\ G dom DProd S ) -> ( A e. ( G DProd S ) <-> E. f e. W A = ( G gsumg f ) ) )
16	15	pm5.32da 673	. 2 |- ( dom S = I -> ( ( G dom DProd S /\ A e. ( G DProd S ) ) <-> ( G dom DProd S /\ E. f e. W A = ( G gsumg f ) ) ) )
17	6, 16	syl5bb 272	1 |- ( dom S = I -> ( A e. ( G DProd S ) <-> ( G dom DProd S /\ E. f e. W A = ( G gsumg f ) ) ) )

Syntax hints:   -> wi 4   <-> wb 196   /\ wa 384   = wceq 1483   e. wcel 1990   E.wrex 2913   {crab 2916   <.cop 4183   class class class wbr 4653   |-> cmpt 4729   dom cdm 5114   ran crn 5115   ` cfv 5888  (class class class)co 6650   X_cixp 7908   finSupp cfsupp 8275   0gc0g 16100   gsum_g cgsu 16101   DProd cdprd 18392

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-rep 4771  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-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-reu 2919  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-op 4184  df-uni 4437  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-id 5024  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-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-1st 7168  df-2nd 7169  df-ixp 7909  df-dprd 18394

This theorem is referenced by:  dprdssv  18415  eldprdi  18417  dprdsubg  18423  dprdss  18428  dmdprdsplitlem  18436  dprddisj2  18438  dpjidcl  18457