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| n | a(n) |
|---|---|
| 1 | 81 |
| 2 | 549 |
| 3 | 549 |
| 4 | 3459 |
| 5 | 8678 |
| 6 | 3459 |
| 7 | 20537 |
| 8 | 125917 |
| 9 | 125917 |
| 10 | 20537 |
| 11 | 118383 |
| 12 | 1660676 |
| 13 | 4421414 |
| 14 | 1660676 |
| 15 | 118383 |
| 16 | 668041 |
| 17 | 20719004 |
| 18 | 140378037 |
| 19 | 140378037 |
| 20 | 20719004 |
| 21 | 668041 |
| 22 | 3720671 |
| 23 | 246491295 |
| 24 | 4163928036 |
| 25 | 11284713813 |
| 26 | 4163928036 |
| 27 | 246491295 |
[81,549,549,3459,8678,3459,20537,125917,125917, 20537,118383,1660676,4421414,1660676,118383, 668041,20719004,140378037,140378037,20719004, 668041,3720671,246491295,4163928036,11284713813, 4163928036,246491295] |