n | a(n) |
---|---|
0 | 1 |
1 | 21 |
2 | 230 |
3 | 1750 |
4 | 10394 |
5 | 51338 |
6 | 219373 |
7 | 833129 |
8 | 2867249 |
9 | 9073845 |
10 | 26706681 |
11 | 73769301 |
12 | 192639951 |
13 | 478480891 |
14 | 1136148412 |
15 | 2590157556 |
16 | 5690334091 |
17 | 12085148911 |
18 | 24881271591 |
19 | 49780020675 |
20 | 96990931345 |
21 | 184385864444 |
[1,21,230,1750,10394,51338,219373,833129,2867249, 9073845,26706681,73769301,192639951,478480891, 1136148412,2590157556,5690334091,12085148911, 24881271591,49780020675,96990931345,184385864444] |