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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 98 |
| 8 | 3328 |
| 9 | 17496 |
| 10 | 99600 |
| 11 | 316052 |
| 12 | 1041408 |
| 13 | 2501538 |
| 14 | 6157536 |
| 15 | 12531150 |
| 16 | 25938944 |
| 17 | 47168268 |
| 18 | 86938272 |
| 19 | 145818008 |
| 20 | 247240000 |
| 21 | 390084786 |
| 22 | 620964256 |
| 23 | 933865918 |
| 24 | 1414946304 |
| 25 | 2047225000 |
| 26 | 2980849040 |
| 27 | 4177648224 |
| 28 | 5886858432 |
| 29 | 8032809818 |
| 30 | 11012886000 |
| 31 | 14689386642 |
| 32 | 19674427392 |
| 33 | 25732782504 |
| 34 | 33779841296 |
| 35 | 43433208000 |
| 36 | 56027023488 |
| 37 | 70963952198 |
| 38 | 90145026976 |
| 39 | 112667956362 |
| 40 | 141187744000 |
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