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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -4 |
| 2 | 14 |
| 3 | -40 |
| 4 | 80 |
| 5 | -64 |
| 6 | -16 |
| 7 | -1600 |
| 8 | 8960 |
| 9 | 29696 |
| 10 | -349696 |
| 11 | -1423360 |
| 12 | 22384640 |
| 13 | 89440256 |
| 14 | -1903691776 |
| 15 | -7615160320 |
| 16 | 209865605120 |
| 17 | 839460847616 |
| 18 | -29088884064256 |
| 19 | -116355542548480 |
| 20 | 4951498057318400 |
| 21 | 19805992204107776 |
| 22 | -1015423886490075136 |
[1,-4,14,-40,80,-64,-16,-1600,8960,29696,-349696, -1423360,22384640,89440256,-1903691776, -7615160320,209865605120,839460847616, -29088884064256,-116355542548480,4951498057318400, 19805992204107776,-1015423886490075136] |