Metamath Proof Explorer


Theorem mapfien2

Description: Equinumerousity relation for sets of finitely supported functions. (Contributed by Stefan O'Rear, 9-Jul-2015) (Revised by AV, 7-Jul-2019)

Ref Expression
Hypotheses mapfien2.s S=xBA|finSupp0˙x
mapfien2.t T=xDC|finSuppWx
mapfien2.ac φAC
mapfien2.bd φBD
mapfien2.z φ0˙B
mapfien2.w φWD
Assertion mapfien2 φST

Proof

Step Hyp Ref Expression
1 mapfien2.s S=xBA|finSupp0˙x
2 mapfien2.t T=xDC|finSuppWx
3 mapfien2.ac φAC
4 mapfien2.bd φBD
5 mapfien2.z φ0˙B
6 mapfien2.w φWD
7 enfixsn 0˙BWDBDyy:B1-1 ontoDy0˙=W
8 5 6 4 7 syl3anc φyy:B1-1 ontoDy0˙=W
9 bren ACzz:A1-1 ontoC
10 3 9 sylib φzz:A1-1 ontoC
11 eqid xDC|finSuppy0˙x=xDC|finSuppy0˙x
12 eqid y0˙=y0˙
13 f1ocnv z:A1-1 ontoCz-1:C1-1 ontoA
14 13 3ad2ant2 φz:A1-1 ontoCy:B1-1 ontoDz-1:C1-1 ontoA
15 simp3 φz:A1-1 ontoCy:B1-1 ontoDy:B1-1 ontoD
16 3 3ad2ant1 φz:A1-1 ontoCy:B1-1 ontoDAC
17 relen Rel
18 17 brrelex1i ACAV
19 16 18 syl φz:A1-1 ontoCy:B1-1 ontoDAV
20 4 3ad2ant1 φz:A1-1 ontoCy:B1-1 ontoDBD
21 17 brrelex1i BDBV
22 20 21 syl φz:A1-1 ontoCy:B1-1 ontoDBV
23 17 brrelex2i ACCV
24 16 23 syl φz:A1-1 ontoCy:B1-1 ontoDCV
25 17 brrelex2i BDDV
26 20 25 syl φz:A1-1 ontoCy:B1-1 ontoDDV
27 5 3ad2ant1 φz:A1-1 ontoCy:B1-1 ontoD0˙B
28 1 11 12 14 15 19 22 24 26 27 mapfien φz:A1-1 ontoCy:B1-1 ontoDwSywz-1:S1-1 ontoxDC|finSuppy0˙x
29 ovex BAV
30 1 29 rabex2 SV
31 30 f1oen wSywz-1:S1-1 ontoxDC|finSuppy0˙xSxDC|finSuppy0˙x
32 28 31 syl φz:A1-1 ontoCy:B1-1 ontoDSxDC|finSuppy0˙x
33 32 3adant3r φz:A1-1 ontoCy:B1-1 ontoDy0˙=WSxDC|finSuppy0˙x
34 breq2 y0˙=WfinSuppy0˙xfinSuppWx
35 34 rabbidv y0˙=WxDC|finSuppy0˙x=xDC|finSuppWx
36 35 2 eqtr4di y0˙=WxDC|finSuppy0˙x=T
37 36 adantl y:B1-1 ontoDy0˙=WxDC|finSuppy0˙x=T
38 37 3ad2ant3 φz:A1-1 ontoCy:B1-1 ontoDy0˙=WxDC|finSuppy0˙x=T
39 33 38 breqtrd φz:A1-1 ontoCy:B1-1 ontoDy0˙=WST
40 39 3exp φz:A1-1 ontoCy:B1-1 ontoDy0˙=WST
41 40 exlimdv φzz:A1-1 ontoCy:B1-1 ontoDy0˙=WST
42 10 41 mpd φy:B1-1 ontoDy0˙=WST
43 42 exlimdv φyy:B1-1 ontoDy0˙=WST
44 8 43 mpd φST