Description: If a member of a finite set of sequential integers with a lower bound being a member of a finite set of sequential nonnegative integers with the same upper bound, this member is also a member of the finite set of sequential nonnegative integers. (Contributed by Alexander van der Vekens, 21-Apr-2018)
Ref | Expression | ||
---|---|---|---|
Assertion | fz0fzelfz0 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elfz2nn0 | |
|
2 | elfz2 | |
|
3 | simplr | |
|
4 | 0red | |
|
5 | nn0re | |
|
6 | 5 | adantr | |
7 | zre | |
|
8 | 7 | adantl | |
9 | 4 6 8 | 3jca | |
10 | 9 | adantr | |
11 | nn0ge0 | |
|
12 | 11 | adantr | |
13 | 12 | anim1i | |
14 | letr | |
|
15 | 10 13 14 | sylc | |
16 | elnn0z | |
|
17 | 3 15 16 | sylanbrc | |
18 | 17 | exp31 | |
19 | 18 | com23 | |
20 | 19 | 3ad2ant1 | |
21 | 20 | com13 | |
22 | 21 | adantrd | |
23 | 22 | 3ad2ant3 | |
24 | 23 | imp | |
25 | 24 | imp | |
26 | simpr2 | |
|
27 | simplrr | |
|
28 | 25 26 27 | 3jca | |
29 | 28 | ex | |
30 | 2 29 | sylbi | |
31 | 30 | com12 | |
32 | 1 31 | sylbi | |
33 | 32 | imp | |
34 | elfz2nn0 | |
|
35 | 33 34 | sylibr | |