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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 255 |
| 3 | 221 |
| 4 | 4216 |
| 5 | 4114 |
| 6 | 35666 |
| 7 | 37536 |
| 8 | 221085 |
| 9 | 244545 |
| 10 | 1112803 |
| 11 | 1278196 |
| 12 | 4849046 |
| 13 | 5728337 |
| 14 | 18897557 |
| 15 | 22823928 |
| 16 | 67443437 |
| 17 | 82879982 |
| 18 | 223825825 |
| 19 | 278900776 |
| 20 | 698899427 |
| 21 | 880590786 |
| 22 | 2071022977 |
| 23 | 2632885030 |
| 24 | 5864089905 |
| 25 | 7508811906 |
| 26 | 15951383169 |
| 27 | 20543782345 |
[1,0,255,221,4216,4114,35666,37536,221085,244545, 1112803,1278196,4849046,5728337,18897557,22823928, 67443437,82879982,223825825,278900776,698899427, 880590786,2071022977,2632885030,5864089905, 7508811906,15951383169,20543782345] |