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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 1 |
| 4 | -2 |
| 5 | -1 |
| 6 | 1 |
| 7 | -6 |
| 8 | -7 |
| 9 | 0 |
| 10 | 1 |
| 11 | -24 |
| 12 | -38 |
| 13 | -13 |
| 14 | 2 |
| 15 | 1 |
| 16 | -120 |
| 17 | -226 |
| 18 | -125 |
| 19 | -15 |
| 20 | 5 |
| 21 | 1 |
| 22 | -720 |
| 23 | -1524 |
| 24 | -1076 |
| 25 | -285 |
| 26 | -5 |
| 27 | 9 |
| 28 | 1 |
| 29 | -5040 |
| 30 | -11628 |
| 31 | -9604 |
| 32 | -3521 |
| 33 | -490 |
| 34 | 28 |
| 35 | 14 |
| 36 | 1 |
| 37 | -40320 |
| 38 | -99504 |
| 39 | -91988 |
| 40 | -41020 |
| 41 | -8911 |
| 42 | -616 |
| 43 | 98 |
| 44 | 20 |
| 45 | 1 |
| 46 | -362880 |
| 47 | -945936 |
| 48 | -953532 |
| 49 | -487432 |
| 50 | -134757 |
| 51 | -18375 |
| 52 | -378 |
| 53 | 222 |
| 54 | 27 |
| 55 | 1 |
| 56 | -3628800 |
[1,-1,1,-2,-1,1,-6,-7,0,1,-24,-38,-13,2,1,-120, -226,-125,-15,5,1,-720,-1524,-1076,-285,-5,9,1, -5040,-11628,-9604,-3521,-490,28,14,1,-40320, -99504,-91988,-41020,-8911,-616,98,20,1,-362880, -945936,-953532,-487432,-134757,-18375,-378,222, 27,1,-3628800] |