Description: The property of being a cluster point of a function. (Contributed by Jeff Hankins, 24-Nov-2009) (Revised by Stefan O'Rear, 9-Aug-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | isfcf | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | fcfval | |
|
2 | 1 | eleq2d | |
3 | simp1 | |
|
4 | toponmax | |
|
5 | filfbas | |
|
6 | id | |
|
7 | fmfil | |
|
8 | 4 5 6 7 | syl3an | |
9 | fclsopn | |
|
10 | 3 8 9 | syl2anc | |
11 | simpll1 | |
|
12 | 11 4 | syl | |
13 | simpll2 | |
|
14 | 13 5 | syl | |
15 | simpll3 | |
|
16 | simpl2 | |
|
17 | fgfil | |
|
18 | 16 17 | syl | |
19 | 18 | eleq2d | |
20 | 19 | biimpar | |
21 | eqid | |
|
22 | 21 | imaelfm | |
23 | 12 14 15 20 22 | syl31anc | |
24 | ineq2 | |
|
25 | 24 | neeq1d | |
26 | 25 | rspcv | |
27 | 23 26 | syl | |
28 | 27 | ralrimdva | |
29 | elfm | |
|
30 | 4 5 6 29 | syl3an | |
31 | 30 | adantr | |
32 | 31 | simplbda | |
33 | r19.29r | |
|
34 | sslin | |
|
35 | ssn0 | |
|
36 | 34 35 | sylan | |
37 | 36 | rexlimivw | |
38 | 33 37 | syl | |
39 | 38 | ex | |
40 | 32 39 | syl | |
41 | 40 | ralrimdva | |
42 | 28 41 | impbid | |
43 | 42 | imbi2d | |
44 | 43 | ralbidva | |
45 | 44 | anbi2d | |
46 | 2 10 45 | 3bitrd | |