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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 18 |
| 6 | 18 |
| 7 | 6 |
| 8 | 156 |
| 9 | 432 |
| 10 | 288 |
| 11 | 24 |
| 12 | 792 |
| 13 | 7416 |
| 14 | 13248 |
| 15 | 6624 |
| 16 | 120 |
| 17 | -11280 |
| 18 | 64800 |
| 19 | 374400 |
| 20 | 496800 |
| 21 | 198720 |
| 22 | 720 |
| 23 | -62640 |
| 24 | -1254960 |
| 25 | 4968000 |
| 26 | 20865600 |
| 27 | 22057920 |
| 28 | 7352640 |
| 29 | 5040 |
| 30 | 24012000 |
| 31 | -11854080 |
| 32 | -125677440 |
| 33 | 389491200 |
| 34 | 1288103040 |
[1,1,2,2,18,18,6,156,432,288,24,792,7416,13248, 6624,120,-11280,64800,374400,496800,198720,720, -62640,-1254960,4968000,20865600,22057920,7352640, 5040,24012000,-11854080,-125677440,389491200, 1288103040] |