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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | -4 |
| 3 | 126 |
| 4 | -3368 |
| 5 | 95770 |
| 6 | -4408812 |
| 7 | 265489238 |
| 8 | -18154718416 |
| 9 | 1485105153714 |
| 10 | -146642787086420 |
| 11 | 16695614806747822 |
| 12 | -2147275569222109944 |
| 13 | 312504772665433249226 |
| 14 | -51165984479663630172988 |
| 15 | 9306072483765112492581510 |
[0,2,-4,126,-3368,95770,-4408812,265489238, -18154718416,1485105153714,-146642787086420, 16695614806747822,-2147275569222109944, 312504772665433249226,-51165984479663630172988, 9306072483765112492581510] |