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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 260 |
| 3 | 960 |
| 4 | 3060 |
| 5 | 8704 |
| 6 | 16320 |
| 7 | 28800 |
| 8 | 53300 |
| 9 | 87040 |
| 10 | 127944 |
| 11 | 175680 |
| 12 | 262080 |
| 13 | 391680 |
| 14 | 489600 |
| 15 | 600960 |
| 16 | 835380 |
| 17 | 1131520 |
| 18 | 1336900 |
| 19 | 1563840 |
| 20 | 2054824 |
| 21 | 2611200 |
| 22 | 2986560 |
| 23 | 3358080 |
| 24 | 4194240 |
| 25 | 5326848 |
| 26 | 5859400 |
[1,0,260,960,3060,8704,16320,28800,53300,87040, 127944,175680,262080,391680,489600,600960,835380, 1131520,1336900,1563840,2054824,2611200,2986560, 3358080,4194240,5326848,5859400] |