| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 750 |
| 5 | 7770 |
| 6 | 52675 |
| 7 | 449550 |
| 8 | 2311575 |
| 9 | 8624700 |
| 10 | 22661835 |
| 11 | 42102850 |
| 12 | 57811425 |
| 13 | 58254700 |
| 14 | 42267025 |
| 15 | 22408050 |
| 16 | 8633100 |
| 17 | 2316300 |
| 18 | 470625 |
| 19 | 61950 |
| 20 | 525 |
| 21 | 50 |
| 22 | 0 |
| 23 | 0 |
| 24 | 0 |
| 25 | 1 |
[1,0,0,0,750,7770,52675,449550,2311575,8624700, 22661835,42102850,57811425,58254700,42267025, 22408050,8633100,2316300,470625,61950,525,50,0,0, 0,1] |