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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 1 |
| 4 | -20 |
| 5 | -151 |
| 6 | -354 |
| 7 | 6217 |
| 8 | 100472 |
| 9 | 537777 |
| 10 | -7631270 |
| 11 | -223395919 |
| 12 | -2120164188 |
| 13 | 22050300505 |
| 14 | 1154262915638 |
| 15 | 17130776734905 |
| 16 | -105423782758544 |
| 17 | -11372993234072863 |
| 18 | -245877012220234446 |
| 19 | 345837436238423521 |
| 20 | 188329590656514108380 |
[0,1,2,1,-20,-151,-354,6217,100472,537777, -7631270,-223395919,-2120164188,22050300505, 1154262915638,17130776734905,-105423782758544, -11372993234072863,-245877012220234446, 345837436238423521,188329590656514108380] |