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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 3 |
| 9 | 4 |
| 10 | 24 |
| 11 | 30 |
| 12 | 105 |
| 13 | 126 |
| 14 | 336 |
| 15 | 392 |
| 16 | 882 |
| 17 | 1008 |
| 18 | 2044 |
| 19 | 2304 |
| 20 | 4554 |
| 21 | 5115 |
| 22 | 10890 |
| 23 | 12342 |
| 24 | 29887 |
| 25 | 34320 |
| 26 | 90090 |
| 27 | 104104 |
| 28 | 273559 |
| 29 | 315679 |
| 30 | 795704 |
| 31 | 913640 |
| 32 | 2196740 |
| 33 | 2508928 |
| 34 | 5845008 |
[0,0,0,0,0,0,0,3,4,24,30,105,126,336,392,882,1008, 2044,2304,4554,5115,10890,12342,29887,34320,90090, 104104,273559,315679,795704,913640,2196740, 2508928,5845008] |