Description: A point covered by a point-finite cover is only covered by finitely many elements. (Contributed by Jeff Hankins, 21-Jan-2010)
Ref | Expression | ||
---|---|---|---|
Hypothesis | ptfinfin.1 | |
|
Assertion | ptfinfin | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ptfinfin.1 | |
|
2 | 1 | isptfin | |
3 | 2 | ibi | |
4 | eleq1 | |
|
5 | 4 | rabbidv | |
6 | 5 | eleq1d | |
7 | 6 | rspccv | |
8 | 3 7 | syl | |
9 | 8 | imp | |