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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 12 |
| 9 | 60 |
| 10 | 180 |
| 11 | 432 |
| 12 | 900 |
| 13 | 1692 |
| 14 | 2940 |
| 15 | 4800 |
| 16 | 7452 |
| 17 | 11100 |
| 18 | 15972 |
| 19 | 22320 |
| 20 | 30420 |
| 21 | 40572 |
| 22 | 53100 |
| 23 | 68352 |
| 24 | 86700 |
| 25 | 108540 |
| 26 | 134292 |
| 27 | 164400 |
| 28 | 199332 |
| 29 | 239580 |
| 30 | 285660 |
| 31 | 338112 |
| 32 | 397500 |
| 33 | 464412 |
| 34 | 539460 |
| 35 | 623280 |
| 36 | 716532 |
| 37 | 819900 |
| 38 | 934092 |
| 39 | 1059840 |
[0,0,0,0,0,0,0,12,60,180,432,900,1692,2940,4800, 7452,11100,15972,22320,30420,40572,53100,68352, 86700,108540,134292,164400,199332,239580,285660, 338112,397500,464412,539460,623280,716532,819900, 934092,1059840] |