n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 3 |
4 | 15 |
5 | 87 |
6 | 687 |
7 | 6447 |
8 | 71967 |
9 | 918687 |
10 | 13256607 |
11 | 212840607 |
12 | 3765435807 |
13 | 72741666207 |
14 | 1523637512607 |
15 | 34389853295007 |
16 | 832071217775007 |
17 | 21482864837231007 |
18 | 589515687506543007 |
19 | 17133249343107695007 |
20 | 525731414152434287007 |
21 | 16984313499467403887007 |
[0,1,3,15,87,687,6447,71967,918687,13256607, 212840607,3765435807,72741666207,1523637512607, 34389853295007,832071217775007,21482864837231007, 589515687506543007,17133249343107695007, 525731414152434287007,16984313499467403887007] |