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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 9 |
| 6 | 0 |
| 7 | 0 |
| 8 | 56 |
| 9 | 56 |
| 10 | 0 |
| 11 | 0 |
| 12 | 378 |
| 13 | 1107 |
| 14 | 378 |
| 15 | 0 |
| 16 | 0 |
| 17 | 2475 |
| 18 | 27692 |
| 19 | 27692 |
| 20 | 2475 |
| 21 | 0 |
| 22 | 0 |
| 23 | 16256 |
| 24 | 657057 |
| 25 | 2341962 |
| 26 | 657057 |
| 27 | 16256 |
| 28 | 0 |
| 29 | 0 |
| 30 | 106629 |
| 31 | 15710423 |
| 32 | 197382906 |
| 33 | 197382906 |
| 34 | 15710423 |
| 35 | 106629 |
| 36 | 0 |
| 37 | 0 |
| 38 | 699390 |
| 39 | 374768765 |
| 40 | 16607042116 |
[0,0,0,0,9,0,0,56,56,0,0,378,1107,378,0,0,2475, 27692,27692,2475,0,0,16256,657057,2341962,657057, 16256,0,0,106629,15710423,197382906,197382906, 15710423,106629,0,0,699390,374768765,16607042116] |