Metamath Proof Explorer


Theorem islocfin

Description: The statement "is a locally finite cover." (Contributed by Jeff Hankins, 21-Jan-2010)

Ref Expression
Hypotheses islocfin.1 X=J
islocfin.2 Y=A
Assertion islocfin ALocFinJJTopX=YxXnJxnsA|snFin

Proof

Step Hyp Ref Expression
1 islocfin.1 X=J
2 islocfin.2 Y=A
3 df-locfin LocFin=jTopy|j=yxjnjxnsy|snFin
4 3 mptrcl ALocFinJJTop
5 eqimss2 X=yyX
6 sspwuni y𝒫XyX
7 5 6 sylibr X=yy𝒫X
8 velpw y𝒫𝒫Xy𝒫X
9 7 8 sylibr X=yy𝒫𝒫X
10 9 adantr X=yxXnJxnsy|snFiny𝒫𝒫X
11 10 abssi y|X=yxXnJxnsy|snFin𝒫𝒫X
12 1 topopn JTopXJ
13 pwexg XJ𝒫XV
14 pwexg 𝒫XV𝒫𝒫XV
15 12 13 14 3syl JTop𝒫𝒫XV
16 ssexg y|X=yxXnJxnsy|snFin𝒫𝒫X𝒫𝒫XVy|X=yxXnJxnsy|snFinV
17 11 15 16 sylancr JTopy|X=yxXnJxnsy|snFinV
18 unieq j=Jj=J
19 18 1 eqtr4di j=Jj=X
20 19 eqeq1d j=Jj=yX=y
21 rexeq j=Jnjxnsy|snFinnJxnsy|snFin
22 19 21 raleqbidv j=Jxjnjxnsy|snFinxXnJxnsy|snFin
23 20 22 anbi12d j=Jj=yxjnjxnsy|snFinX=yxXnJxnsy|snFin
24 23 abbidv j=Jy|j=yxjnjxnsy|snFin=y|X=yxXnJxnsy|snFin
25 24 3 fvmptg JTopy|X=yxXnJxnsy|snFinVLocFinJ=y|X=yxXnJxnsy|snFin
26 17 25 mpdan JTopLocFinJ=y|X=yxXnJxnsy|snFin
27 26 eleq2d JTopALocFinJAy|X=yxXnJxnsy|snFin
28 elex Ay|X=yxXnJxnsy|snFinAV
29 28 adantl JTopAy|X=yxXnJxnsy|snFinAV
30 simpr JTopX=YX=Y
31 30 2 eqtrdi JTopX=YX=A
32 12 adantr JTopX=YXJ
33 31 32 eqeltrrd JTopX=YAJ
34 33 elexd JTopX=YAV
35 uniexb AVAV
36 34 35 sylibr JTopX=YAV
37 36 adantrr JTopX=YxXnJxnsA|snFinAV
38 unieq y=Ay=A
39 38 2 eqtr4di y=Ay=Y
40 39 eqeq2d y=AX=yX=Y
41 rabeq y=Asy|sn=sA|sn
42 41 eleq1d y=Asy|snFinsA|snFin
43 42 anbi2d y=Axnsy|snFinxnsA|snFin
44 43 rexbidv y=AnJxnsy|snFinnJxnsA|snFin
45 44 ralbidv y=AxXnJxnsy|snFinxXnJxnsA|snFin
46 40 45 anbi12d y=AX=yxXnJxnsy|snFinX=YxXnJxnsA|snFin
47 46 elabg AVAy|X=yxXnJxnsy|snFinX=YxXnJxnsA|snFin
48 29 37 47 pm5.21nd JTopAy|X=yxXnJxnsy|snFinX=YxXnJxnsA|snFin
49 27 48 bitrd JTopALocFinJX=YxXnJxnsA|snFin
50 4 49 biadanii ALocFinJJTopX=YxXnJxnsA|snFin
51 3anass JTopX=YxXnJxnsA|snFinJTopX=YxXnJxnsA|snFin
52 50 51 bitr4i ALocFinJJTopX=YxXnJxnsA|snFin