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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | -2 |
| 5 | 6 |
| 6 | -17 |
| 7 | 49 |
| 8 | -141 |
| 9 | 406 |
| 10 | -1169 |
| 11 | 3366 |
| 12 | -9692 |
| 13 | 27907 |
| 14 | -80355 |
| 15 | 231373 |
| 16 | -666212 |
| 17 | 1918281 |
| 18 | -5523470 |
| 19 | 15904198 |
| 20 | -45794313 |
| 21 | 131859469 |
| 22 | -379674209 |
| 23 | 1093228314 |
| 24 | -3147825473 |
| 25 | 9063802210 |
| 26 | -26098178316 |
| 27 | 75146709475 |
| 28 | -216376326215 |
| 29 | 623030800329 |
| 30 | -1793945691512 |
| 31 | 5165460748321 |
[1,1,0,1,-2,6,-17,49,-141,406,-1169,3366,-9692, 27907,-80355,231373,-666212,1918281,-5523470, 15904198,-45794313,131859469,-379674209, 1093228314,-3147825473,9063802210,-26098178316, 75146709475,-216376326215,623030800329, -1793945691512,5165460748321] |