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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 10 |
| 8 | 20 |
| 9 | 35 |
| 10 | 105 |
| 11 | 168 |
| 12 | 252 |
| 13 | 588 |
| 14 | 930 |
| 15 | 1452 |
| 16 | 3960 |
| 17 | 6820 |
| 18 | 11440 |
| 19 | 30745 |
| 20 | 52507 |
| 21 | 86905 |
| 22 | 219765 |
| 23 | 372120 |
| 24 | 617610 |
| 25 | 1572228 |
| 26 | 2702252 |
| 27 | 4563344 |
| 28 | 11666760 |
| 29 | 20167170 |
| 30 | 34220634 |
| 31 | 86461704 |
| 32 | 149465844 |
| 33 | 254222289 |
| 34 | 639438019 |
[0,0,0,0,0,0,10,20,35,105,168,252,588,930,1452, 3960,6820,11440,30745,52507,86905,219765,372120, 617610,1572228,2702252,4563344,11666760,20167170, 34220634,86461704,149465844,254222289,639438019] |