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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 12 |
| 7 | 24 |
| 8 | 132 |
| 9 | 240 |
| 10 | 900 |
| 11 | 1560 |
| 12 | 4968 |
| 13 | 8400 |
| 14 | 24588 |
| 15 | 40824 |
| 16 | 113520 |
| 17 | 186480 |
| 18 | 502248 |
| 19 | 818520 |
| 20 | 2157360 |
| 21 | 3497976 |
| 22 | 9085452 |
| 23 | 14676024 |
| 24 | 37723260 |
| 25 | 60780720 |
| 26 | 155082900 |
| 27 | 249401640 |
| 28 | 632947728 |
| 29 | 1016542800 |
| 30 | 2569816476 |
| 31 | 4123173624 |
| 32 | 10393520640 |
[0,0,0,0,0,12,24,132,240,900,1560,4968,8400,24588, 40824,113520,186480,502248,818520,2157360,3497976, 9085452,14676024,37723260,60780720,155082900, 249401640,632947728,1016542800,2569816476, 4123173624,10393520640] |