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| n | a(n) |
|---|---|
| 8 | 1 |
| 9 | 0 |
| 10 | 45 |
| 11 | 330 |
| 12 | 4455 |
| 13 | 56628 |
| 14 | 795795 |
| 15 | 11930490 |
| 16 | 190900710 |
| 17 | 3245287760 |
| 18 | 58415223438 |
| 19 | 1109889169740 |
| 20 | 22197783520770 |
| 21 | 466153453732680 |
| 22 | 10255375982438730 |
| 23 | 235873647595600476 |
| 24 | 5660967542295146895 |
| 25 | 141524188557377590800 |
[1,0,45,330,4455,56628,795795,11930490,190900710, 3245287760,58415223438,1109889169740, 22197783520770,466153453732680,10255375982438730, 235873647595600476,5660967542295146895, 141524188557377590800] |