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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 27 |
| 4 | 272 |
| 5 | 1625 |
| 6 | 6993 |
| 7 | 24010 |
| 8 | 69888 |
| 9 | 179334 |
| 10 | 416625 |
| 11 | 893101 |
| 12 | 1791504 |
| 13 | 3398759 |
| 14 | 6148961 |
| 15 | 10678500 |
| 16 | 17895424 |
| 17 | 29065308 |
| 18 | 45916065 |
| 19 | 70764303 |
| 20 | 106666000 |
| 21 | 157594437 |
| 22 | 228648497 |
| 23 | 326294606 |
| 24 | 458645760 |
| 25 | 635781250 |
| 26 | 870110865 |
| 27 | 1176787521 |
| 28 | 1574172432 |
| 29 | 2084357107 |
[0,0,1,27,272,1625,6993,24010,69888,179334,416625, 893101,1791504,3398759,6148961,10678500,17895424, 29065308,45916065,70764303,106666000,157594437, 228648497,326294606,458645760,635781250,870110865, 1176787521,1574172432,2084357107] |