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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -2 |
| 3 | 7 |
| 4 | -26 |
| 5 | 102 |
| 6 | -420 |
| 7 | 1787 |
| 8 | -7794 |
| 9 | 34666 |
| 10 | -156636 |
| 11 | 716982 |
| 12 | -3317700 |
| 13 | 15494156 |
| 14 | -72935624 |
| 15 | 345701843 |
| 16 | -1648489762 |
| 17 | 7902956738 |
| 18 | -38067806892 |
| 19 | 184152092450 |
| 20 | -894259126540 |
| 21 | 4357738501844 |
| 22 | -21302682030328 |
| 23 | 104439435098718 |
| 24 | -513390992000340 |
| 25 | 2529846489669412 |
| 26 | -12494572784556440 |
| 27 | 61838364112438732 |
| 28 | -306647601790749384 |
| 29 | 1523380558254732312 |
| 30 | -7580755340625743760 |
| 31 | 37783723921640161923 |
[1,1,-2,7,-26,102,-420,1787,-7794,34666,-156636, 716982,-3317700,15494156,-72935624,345701843, -1648489762,7902956738,-38067806892,184152092450, -894259126540,4357738501844,-21302682030328, 104439435098718,-513390992000340,2529846489669412, -12494572784556440,61838364112438732, -306647601790749384,1523380558254732312, -7580755340625743760,37783723921640161923] |