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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 9 |
| 5 | 45 |
| 6 | 135 |
| 7 | 315 |
| 8 | 630 |
| 9 | 1134 |
| 10 | 1890 |
| 11 | 2970 |
| 12 | 4455 |
| 13 | 6435 |
| 14 | 9009 |
| 15 | 12285 |
| 16 | 16380 |
| 17 | 21420 |
| 18 | 27540 |
| 19 | 34884 |
| 20 | 43605 |
| 21 | 53865 |
| 22 | 65835 |
| 23 | 79695 |
| 24 | 95634 |
| 25 | 113850 |
| 26 | 134550 |
| 27 | 157950 |
| 28 | 184275 |
| 29 | 213759 |
| 30 | 246645 |
| 31 | 283185 |
| 32 | 323640 |
| 33 | 368280 |
| 34 | 417384 |
| 35 | 471240 |
| 36 | 530145 |
| 37 | 594405 |
[0,0,0,0,9,45,135,315,630,1134,1890,2970,4455, 6435,9009,12285,16380,21420,27540,34884,43605, 53865,65835,79695,95634,113850,134550,157950, 184275,213759,246645,283185,323640,368280,417384, 471240,530145,594405] |