Description: Condition for a function over the nonnegative integers to have a support contained in a finite set of sequential integers. (Contributed by AV, 9-Oct-2019)
Ref | Expression | ||
---|---|---|---|
Hypotheses | suppssfz.z | |
|
suppssfz.f | |
||
suppssfz.s | |
||
suppssfz.b | |
||
Assertion | suppssfz | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | suppssfz.z | |
|
2 | suppssfz.f | |
|
3 | suppssfz.s | |
|
4 | suppssfz.b | |
|
5 | elmapfn | |
|
6 | 2 5 | syl | |
7 | nn0ex | |
|
8 | 7 | a1i | |
9 | 6 8 1 | 3jca | |
10 | 9 | adantr | |
11 | elsuppfn | |
|
12 | 10 11 | syl | |
13 | breq2 | |
|
14 | fveqeq2 | |
|
15 | 13 14 | imbi12d | |
16 | 15 | rspcva | |
17 | simplr | |
|
18 | 3 | adantr | |
19 | 18 | adantr | |
20 | nn0re | |
|
21 | nn0re | |
|
22 | 3 21 | syl | |
23 | lenlt | |
|
24 | 20 22 23 | syl2anr | |
25 | 24 | biimpar | |
26 | elfz2nn0 | |
|
27 | 17 19 25 26 | syl3anbrc | |
28 | 27 | a1d | |
29 | 28 | ex | |
30 | eqneqall | |
|
31 | 30 | a1i | |
32 | 29 31 | jad | |
33 | 32 | com23 | |
34 | 33 | ex | |
35 | 34 | com14 | |
36 | 16 35 | syl | |
37 | 36 | ex | |
38 | 37 | pm2.43a | |
39 | 38 | com23 | |
40 | 39 | imp | |
41 | 40 | com13 | |
42 | 41 | imp | |
43 | 12 42 | sylbid | |
44 | 43 | ssrdv | |
45 | 4 44 | mpdan | |