Metamath Proof Explorer


Theorem haustsms2

Description: In a Hausdorff topological group, a sum has at most one limit point. (Contributed by Mario Carneiro, 13-Sep-2015)

Ref Expression
Hypotheses tsmscl.b B = Base G
tsmscl.1 φ G CMnd
tsmscl.2 φ G TopSp
tsmscl.a φ A V
tsmscl.f φ F : A B
haustsms.j J = TopOpen G
haustsms.h φ J Haus
Assertion haustsms2 φ X G tsums F G tsums F = X

Proof

Step Hyp Ref Expression
1 tsmscl.b B = Base G
2 tsmscl.1 φ G CMnd
3 tsmscl.2 φ G TopSp
4 tsmscl.a φ A V
5 tsmscl.f φ F : A B
6 haustsms.j J = TopOpen G
7 haustsms.h φ J Haus
8 simpr φ X G tsums F X G tsums F
9 1 2 3 4 5 6 7 haustsms φ * x x G tsums F
10 9 adantr φ X G tsums F * x x G tsums F
11 eleq1 x = X x G tsums F X G tsums F
12 11 moi2 X G tsums F * x x G tsums F x G tsums F X G tsums F x = X
13 12 ancom2s X G tsums F * x x G tsums F X G tsums F x G tsums F x = X
14 13 expr X G tsums F * x x G tsums F X G tsums F x G tsums F x = X
15 8 10 8 14 syl21anc φ X G tsums F x G tsums F x = X
16 velsn x X x = X
17 15 16 syl6ibr φ X G tsums F x G tsums F x X
18 17 ssrdv φ X G tsums F G tsums F X
19 snssi X G tsums F X G tsums F
20 19 adantl φ X G tsums F X G tsums F
21 18 20 eqssd φ X G tsums F G tsums F = X
22 21 ex φ X G tsums F G tsums F = X