Description: A "diagonal commutation" of divisor sums analogous to fsum0diag . (Contributed by Mario Carneiro, 2-Jul-2015) (Revised by Mario Carneiro, 8-Apr-2016)
Ref | Expression | ||
---|---|---|---|
Hypothesis | fsumdvdsdiag.1 | |
|
Assertion | fsumdvdsdiaglem | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | fsumdvdsdiag.1 | |
|
2 | breq1 | |
|
3 | elrabi | |
|
4 | 3 | ad2antll | |
5 | 4 | nnzd | |
6 | 1 | adantr | |
7 | simprl | |
|
8 | dvdsdivcl | |
|
9 | 6 7 8 | syl2anc | |
10 | elrabi | |
|
11 | 9 10 | syl | |
12 | 11 | nnzd | |
13 | 6 | nnzd | |
14 | breq1 | |
|
15 | 14 | elrab | |
16 | 15 | simprbi | |
17 | 16 | ad2antll | |
18 | breq1 | |
|
19 | 18 | elrab | |
20 | 19 | simprbi | |
21 | 9 20 | syl | |
22 | 5 12 13 17 21 | dvdstrd | |
23 | 2 4 22 | elrabd | |
24 | breq1 | |
|
25 | elrabi | |
|
26 | 25 | ad2antrl | |
27 | 26 | nnzd | |
28 | 26 | nnne0d | |
29 | dvdsmulcr | |
|
30 | 5 12 27 28 29 | syl112anc | |
31 | 17 30 | mpbird | |
32 | 6 | nncnd | |
33 | 26 | nncnd | |
34 | 32 33 28 | divcan1d | |
35 | 4 | nncnd | |
36 | 4 | nnne0d | |
37 | 32 35 36 | divcan2d | |
38 | 34 37 | eqtr4d | |
39 | 31 38 | breqtrd | |
40 | ssrab2 | |
|
41 | dvdsdivcl | |
|
42 | 6 23 41 | syl2anc | |
43 | 40 42 | sselid | |
44 | 43 | nnzd | |
45 | dvdscmulr | |
|
46 | 27 44 5 36 45 | syl112anc | |
47 | 39 46 | mpbid | |
48 | 24 26 47 | elrabd | |
49 | 23 48 | jca | |
50 | 49 | ex | |