n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 2 |
4 | 6 |
5 | 15 |
6 | 40 |
7 | 109 |
8 | 302 |
9 | 846 |
10 | 2390 |
11 | 6796 |
12 | 19426 |
13 | 55767 |
14 | 160668 |
15 | 464305 |
16 | 1345282 |
17 | 3906701 |
18 | 11367696 |
19 | 33135987 |
20 | 96740610 |
21 | 282831981 |
22 | 827939880 |
23 | 2426431239 |
24 | 7118546874 |
25 | 20904025380 |
26 | 61439768166 |
27 | 180725813478 |
28 | 532004277518 |
[0,1,2,6,15,40,109,302,846,2390,6796,19426,55767, 160668,464305,1345282,3906701,11367696,33135987, 96740610,282831981,827939880,2426431239, 7118546874,20904025380,61439768166,180725813478, 532004277518] |