| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 68 |
| 4 | 183 |
| 5 | 535 |
| 6 | 2430 |
| 7 | 12005 |
| 8 | 45977 |
| 9 | 182298 |
| 10 | 793315 |
| 11 | 3484949 |
| 12 | 14803822 |
| 13 | 63574491 |
| 14 | 278058902 |
| 15 | 1219845758 |
| 16 | 5340002947 |
| 17 | 23461452827 |
| 18 | 103504152712 |
| 19 | 457326306914 |
| 20 | 2022170756866 |
| 21 | 8953245703620 |
| 22 | 39687982435839 |
| 23 | 176052243048369 |
[1,6,68,183,535,2430,12005,45977,182298,793315, 3484949,14803822,63574491,278058902,1219845758, 5340002947,23461452827,103504152712,457326306914, 2022170756866,8953245703620,39687982435839, 176052243048369] |