n | a(n) |
---|---|
1 | 0 |
2 | 9 |
3 | 66 |
4 | 256 |
5 | 820 |
6 | 2551 |
7 | 7491 |
8 | 21131 |
9 | 57971 |
10 | 155551 |
11 | 409876 |
12 | 1064002 |
13 | 2727560 |
14 | 6917391 |
15 | 17381168 |
16 | 43320628 |
17 | 107203164 |
18 | 263611545 |
19 | 644549767 |
20 | 1567944409 |
21 | 3796630655 |
22 | 9154650571 |
23 | 21989697066 |
24 | 52634342562 |
25 | 125577952504 |
26 | 298716701553 |
[0,9,66,256,820,2551,7491,21131,57971,155551, 409876,1064002,2727560,6917391,17381168,43320628, 107203164,263611545,644549767,1567944409, 3796630655,9154650571,21989697066,52634342562, 125577952504,298716701553] |