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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 1 |
| 8 | 16 |
| 9 | 136 |
| 10 | 816 |
| 11 | 3876 |
| 12 | 15504 |
| 13 | 54264 |
| 14 | 170544 |
| 15 | 490315 |
| 16 | 1307536 |
| 17 | 3269288 |
| 18 | 7732144 |
| 19 | 17436220 |
| 20 | 37819152 |
| 21 | 79883544 |
| 22 | 167737776 |
| 23 | 362063944 |
| 24 | 839161648 |
| 25 | 2158258904 |
| 26 | 6136548496 |
| 27 | 18586871324 |
| 28 | 57486027952 |
| 29 | 176258492200 |
| 30 | 527387147664 |
| 31 | 1529591016109 |
[0,0,0,0,0,0,0,1,16,136,816,3876,15504,54264, 170544,490315,1307536,3269288,7732144,17436220, 37819152,79883544,167737776,362063944,839161648, 2158258904,6136548496,18586871324,57486027952, 176258492200,527387147664,1529591016109] |