| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 17 |
| 2 | 152 |
| 3 | 952 |
| 4 | 4691 |
| 5 | 19363 |
| 6 | 69615 |
| 7 | 223839 |
| 8 | 656013 |
| 9 | 1777469 |
| 10 | 4501652 |
| 11 | 10749780 |
| 12 | 24374702 |
| 13 | 52784014 |
| 14 | 109694031 |
| 15 | 219658751 |
| 16 | 425310726 |
| 17 | 798645125 |
| 18 | 1458198664 |
| 19 | 2594648817 |
| 20 | 4508215686 |
| 21 | 7662320971 |
| 22 | 12759278753 |
| 23 | 20845394645 |
| 24 | 33454765680 |
[1,17,152,952,4691,19363,69615,223839,656013, 1777469,4501652,10749780,24374702,52784014, 109694031,219658751,425310726,798645125, 1458198664,2594648817,4508215686,7662320971, 12759278753,20845394645,33454765680] |