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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 6 |
| 7 | 21 |
| 8 | 56 |
| 9 | 126 |
| 10 | 252 |
| 11 | 462 |
| 12 | 792 |
| 13 | 1288 |
| 14 | 2016 |
| 15 | 3108 |
| 16 | 4928 |
| 17 | 8569 |
| 18 | 17154 |
| 19 | 38931 |
| 20 | 94164 |
| 21 | 229824 |
| 22 | 550088 |
| 23 | 1278662 |
| 24 | 2884752 |
| 25 | 6335005 |
| 26 | 13590930 |
| 27 | 28575315 |
| 28 | 59014620 |
| 29 | 119878606 |
| 30 | 239662236 |
| 31 | 471605976 |
| 32 | 913302656 |
| 33 | 1740247806 |
| 34 | 3262146492 |
| 35 | 6015853242 |
[0,0,0,0,1,6,21,56,126,252,462,792,1288,2016,3108, 4928,8569,17154,38931,94164,229824,550088,1278662, 2884752,6335005,13590930,28575315,59014620, 119878606,239662236,471605976,913302656, 1740247806,3262146492,6015853242] |