Metamath Proof Explorer


Theorem fmfnfmlem1

Description: Lemma for fmfnfm . (Contributed by Jeff Hankins, 18-Nov-2009) (Revised by Stefan O'Rear, 8-Aug-2015)

Ref Expression
Hypotheses fmfnfm.b φBfBasY
fmfnfm.l φLFilX
fmfnfm.f φF:YX
fmfnfm.fm φXFilMapFBL
Assertion fmfnfmlem1 φsfiBFsttXtL

Proof

Step Hyp Ref Expression
1 fmfnfm.b φBfBasY
2 fmfnfm.l φLFilX
3 fmfnfm.f φF:YX
4 fmfnfm.fm φXFilMapFBL
5 fbssfi BfBasYsfiBwBws
6 1 5 sylan φsfiBwBws
7 sstr2 FwFsFstFwt
8 imass2 wsFwFs
9 7 8 syl11 FstwsFwt
10 9 reximdv FstwBwswBFwt
11 6 10 syl5com φsfiBFstwBFwt
12 filtop LFilXXL
13 2 12 syl φXL
14 elfm XLBfBasYF:YXtXFilMapFBtXwBFwt
15 13 1 3 14 syl3anc φtXFilMapFBtXwBFwt
16 4 sseld φtXFilMapFBtL
17 15 16 sylbird φtXwBFwttL
18 17 expcomd φwBFwttXtL
19 18 adantr φsfiBwBFwttXtL
20 11 19 syld φsfiBFsttXtL
21 20 ex φsfiBFsttXtL