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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -6 |
| 3 | 15 |
| 4 | -26 |
| 5 | 51 |
| 6 | -96 |
| 7 | 136 |
| 8 | -186 |
| 9 | 297 |
| 10 | -422 |
| 11 | 537 |
| 12 | -792 |
| 13 | 1198 |
| 14 | -1608 |
| 15 | 2208 |
| 16 | -3194 |
| 17 | 4290 |
| 18 | -5550 |
| 19 | 7480 |
| 20 | -9906 |
| 21 | 12672 |
| 22 | -16648 |
| 23 | 22038 |
| 24 | -28344 |
| 25 | 36641 |
| 26 | -47796 |
| 27 | 60801 |
| 28 | -76624 |
| 29 | 97710 |
| 30 | -123216 |
| 31 | 153362 |
| 32 | -192954 |
| 33 | 243072 |
| 34 | -302028 |
| 35 | 375639 |
| 36 | -469122 |
| 37 | 579486 |
| 38 | -711432 |
| 39 | 876864 |
[1,-6,15,-26,51,-96,136,-186,297,-422,537,-792, 1198,-1608,2208,-3194,4290,-5550,7480,-9906,12672, -16648,22038,-28344,36641,-47796,60801,-76624, 97710,-123216,153362,-192954,243072,-302028, 375639,-469122,579486,-711432,876864] |