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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | 5 |
| 4 | -47 |
| 5 | 239 |
| 6 | -239 |
| 7 | -11761 |
| 8 | 170689 |
| 9 | -1237825 |
| 10 | -2360159 |
| 11 | 238756319 |
| 12 | -4146035519 |
| 13 | 32586126143 |
| 14 | 359988680689 |
| 15 | -18567245926321 |
| 16 | 351652342984321 |
| 17 | -2283764958280321 |
| 18 | -89760640709677247 |
| 19 | 3866819337993369023 |
| 20 | -74731210747948586879 |
| 21 | 167887841949213912959 |
[1,-1,1,5,-47,239,-239,-11761,170689,-1237825, -2360159,238756319,-4146035519,32586126143, 359988680689,-18567245926321,351652342984321, -2283764958280321,-89760640709677247, 3866819337993369023,-74731210747948586879, 167887841949213912959] |