n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 2 |
4 | 7 |
5 | 28 |
6 | 124 |
7 | 588 |
8 | 2938 |
9 | 15268 |
10 | 81826 |
11 | 449572 |
12 | 2521270 |
13 | 14385376 |
14 | 83290424 |
15 | 488384528 |
16 | 2895432660 |
17 | 17332874364 |
18 | 104653427012 |
19 | 636737003384 |
20 | 3900770002646 |
21 | 24045500114388 |
22 | 149059814328236 |
23 | 928782423033008 |
24 | 5814401613289290 |
25 | 36556766640745936 |
[0,1,2,7,28,124,588,2938,15268,81826,449572, 2521270,14385376,83290424,488384528,2895432660, 17332874364,104653427012,636737003384, 3900770002646,24045500114388,149059814328236, 928782423033008,5814401613289290, 36556766640745936] |