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| n | a(n) |
|---|---|
| 2 | 0 |
| 3 | 0 |
| 4 | 84 |
| 5 | 468 |
| 6 | 1476 |
| 7 | 3540 |
| 8 | 7200 |
| 9 | 13104 |
| 10 | 22008 |
| 11 | 34776 |
| 12 | 52380 |
| 13 | 75900 |
| 14 | 106524 |
| 15 | 145548 |
| 16 | 194376 |
| 17 | 254520 |
| 18 | 327600 |
| 19 | 415344 |
| 20 | 519588 |
| 21 | 642276 |
| 22 | 785460 |
| 23 | 951300 |
| 24 | 1142064 |
| 25 | 1360128 |
| 26 | 1607976 |
| 27 | 1888200 |
| 28 | 2203500 |
| 29 | 2556684 |
| 30 | 2950668 |
| 31 | 3388476 |
[0,0,84,468,1476,3540,7200,13104,22008,34776, 52380,75900,106524,145548,194376,254520,327600, 415344,519588,642276,785460,951300,1142064, 1360128,1607976,1888200,2203500,2556684,2950668, 3388476] |