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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 1 |
| 5 | 12 |
| 6 | 36 |
| 7 | 1 |
| 8 | 72 |
| 9 | 144 |
| 10 | 504 |
| 11 | 1 |
| 12 | 280 |
| 13 | 1800 |
| 14 | 2520 |
| 15 | 9576 |
| 16 | 1 |
| 17 | 1740 |
| 18 | 22320 |
| 19 | 37800 |
| 20 | 57456 |
| 21 | 229824 |
| 22 | 1 |
| 23 | 8484 |
| 24 | 182700 |
| 25 | 864360 |
| 26 | 1005480 |
| 27 | 1608768 |
| 28 | 6664896 |
| 29 | 1 |
| 30 | 57232 |
| 31 | 2380896 |
| 32 | 16546320 |
| 33 | 26276544 |
| 34 | 32175360 |
| 35 | 53319168 |
| 36 | 226606464 |
[1,1,4,1,12,36,1,72,144,504,1,280,1800,2520,9576, 1,1740,22320,37800,57456,229824,1,8484,182700, 864360,1005480,1608768,6664896,1,57232,2380896, 16546320,26276544,32175360,53319168,226606464] |