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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 10 |
| 4 | -21 |
| 5 | 1050 |
| 6 | -45606 |
| 7 | 6306300 |
| 8 | -32585553 |
| 9 | 5332033850 |
| 10 | -646674981498 |
| 11 | 248655336029100 |
| 12 | -579463114572870 |
| 13 | 400708622091878100 |
| 14 | -31790012531476579380 |
| 15 | 43435207772044760997000 |
| 16 | -31514892593265599765292045 |
| 17 | 814247185935070977732893250 |
[-1,1,-1,10,-21,1050,-45606,6306300,-32585553, 5332033850,-646674981498,248655336029100, -579463114572870,400708622091878100, -31790012531476579380,43435207772044760997000, -31514892593265599765292045, 814247185935070977732893250] |