Description: Membership of a sum in a finite interval of integers. (Contributed by Jeff Madsen, 17-Jun-2010)
Ref | Expression | ||
---|---|---|---|
Assertion | fzadd2 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elfz1 | |
|
2 | elfz1 | |
|
3 | 1 2 | bi2anan9 | |
4 | an6 | |
|
5 | zre | |
|
6 | zre | |
|
7 | 5 6 | anim12i | |
8 | zre | |
|
9 | zre | |
|
10 | 8 9 | anim12i | |
11 | le2add | |
|
12 | 7 10 11 | syl2an | |
13 | 12 | impr | |
14 | 13 | 3adantr3 | |
15 | 14 | adantlr | |
16 | zre | |
|
17 | zre | |
|
18 | 16 17 | anim12i | |
19 | le2add | |
|
20 | 10 18 19 | syl2anr | |
21 | 20 | impr | |
22 | 21 | 3adantr2 | |
23 | 22 | adantll | |
24 | zaddcl | |
|
25 | zaddcl | |
|
26 | zaddcl | |
|
27 | elfz | |
|
28 | 24 25 26 27 | syl3an | |
29 | 28 | 3expb | |
30 | 29 | ancoms | |
31 | 30 | 3ad2antr1 | |
32 | 15 23 31 | mpbir2and | |
33 | 32 | ex | |
34 | 33 | an4s | |
35 | 4 34 | biimtrid | |
36 | 3 35 | sylbid | |