Description: Subtracting the lower bound of a finite set of sequential integers from an element of this set. (Contributed by Alexander van der Vekens, 29-Mar-2018)
Ref | Expression | ||
---|---|---|---|
Assertion | elfzmlbp | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elfz2 | |
|
2 | znn0sub | |
|
3 | 2 | adantr | |
4 | 3 | biimpcd | |
5 | 4 | adantr | |
6 | 5 | impcom | |
7 | zre | |
|
8 | 7 | adantr | |
9 | 8 | adantr | |
10 | zre | |
|
11 | 10 | adantl | |
12 | 11 | adantr | |
13 | zaddcl | |
|
14 | 13 | adantlr | |
15 | 14 | zred | |
16 | letr | |
|
17 | 9 12 15 16 | syl3anc | |
18 | zre | |
|
19 | addge01 | |
|
20 | 8 18 19 | syl2an | |
21 | elnn0z | |
|
22 | 21 | simplbi2 | |
23 | 22 | adantl | |
24 | 20 23 | sylbird | |
25 | 17 24 | syld | |
26 | 25 | imp | |
27 | df-3an | |
|
28 | 3ancoma | |
|
29 | 27 28 | bitr3i | |
30 | 10 7 18 | 3anim123i | |
31 | 29 30 | sylbi | |
32 | lesubadd2 | |
|
33 | 31 32 | syl | |
34 | 33 | biimprcd | |
35 | 34 | adantl | |
36 | 35 | impcom | |
37 | 6 26 36 | 3jca | |
38 | 37 | exp31 | |
39 | 38 | com23 | |
40 | 39 | 3adant2 | |
41 | 40 | imp | |
42 | 41 | com12 | |
43 | 1 42 | biimtrid | |
44 | 43 | imp | |
45 | elfz2nn0 | |
|
46 | 44 45 | sylibr | |