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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 3 |
| 3 | 18 |
| 4 | 52 |
| 5 | 117 |
| 6 | 228 |
| 7 | 403 |
| 8 | 663 |
| 9 | 1032 |
| 10 | 1537 |
| 11 | 2208 |
| 12 | 3078 |
| 13 | 4183 |
| 14 | 5562 |
| 15 | 7257 |
| 16 | 9313 |
| 17 | 11778 |
| 18 | 14703 |
| 19 | 18142 |
| 20 | 22152 |
| 21 | 26793 |
| 22 | 32128 |
| 23 | 38223 |
| 24 | 45147 |
| 25 | 52972 |
| 26 | 61773 |
| 27 | 71628 |
| 28 | 82618 |
| 29 | 94827 |
| 30 | 108342 |
| 31 | 123253 |
| 32 | 139653 |
| 33 | 157638 |
| 34 | 177307 |
| 35 | 198762 |
| 36 | 222108 |
| 37 | 247453 |
| 38 | 274908 |
| 39 | 304587 |
[0,0,3,18,52,117,228,403,663,1032,1537,2208,3078, 4183,5562,7257,9313,11778,14703,18142,22152,26793, 32128,38223,45147,52972,61773,71628,82618,94827, 108342,123253,139653,157638,177307,198762,222108, 247453,274908,304587] |