n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 8 |
3 | 55 |
4 | 354 |
5 | 2205 |
6 | 13484 |
7 | 81523 |
8 | 489158 |
9 | 2919481 |
10 | 17356752 |
11 | 102884271 |
12 | 608460330 |
13 | 3591886293 |
14 | 21172419444 |
15 | 124649246955 |
16 | 733107494286 |
17 | 4307974826097 |
18 | 25296523200920 |
19 | 148448166035239 |
20 | 870665283937010 |
[0,1,8,55,354,2205,13484,81523,489158,2919481, 17356752,102884271,608460330,3591886293, 21172419444,124649246955,733107494286, 4307974826097,25296523200920,148448166035239, 870665283937010] |