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| n | a(n) |
|---|---|
| 2 | 0 |
| 3 | 0 |
| 4 | 24 |
| 5 | 312 |
| 6 | 1584 |
| 7 | 5376 |
| 8 | 14448 |
| 9 | 33264 |
| 10 | 68544 |
| 11 | 129888 |
| 12 | 230472 |
| 13 | 387816 |
| 14 | 624624 |
| 15 | 969696 |
| 16 | 1458912 |
| 17 | 2136288 |
| 18 | 3055104 |
| 19 | 4279104 |
| 20 | 5883768 |
| 21 | 7957656 |
| 22 | 10603824 |
| 23 | 13941312 |
| 24 | 18106704 |
| 25 | 23255760 |
| 26 | 29565120 |
| 27 | 37234080 |
| 28 | 46486440 |
| 29 | 57572424 |
| 30 | 70770672 |
| 31 | 86390304 |
| 32 | 104773056 |
| 33 | 126295488 |
[0,0,24,312,1584,5376,14448,33264,68544,129888, 230472,387816,624624,969696,1458912,2136288, 3055104,4279104,5883768,7957656,10603824,13941312, 18106704,23255760,29565120,37234080,46486440, 57572424,70770672,86390304,104773056,126295488] |