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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 27 |
| 4 | 540 |
| 5 | 15273 |
| 6 | 545424 |
| 7 | 23441679 |
| 8 | 1174939901 |
| 9 | 67222626658 |
| 10 | 4321856514871 |
| 11 | 308474127741229 |
| 12 | 24206976396414033 |
| 13 | 2071823443548447053 |
| 14 | 192096343794154776046 |
| 15 | 19183353188372473420096 |
| 16 | 2052995326868420586298713 |
| 17 | 234422512754956257129580893 |
[1,1,2,27,540,15273,545424,23441679,1174939901, 67222626658,4321856514871,308474127741229, 24206976396414033,2071823443548447053, 192096343794154776046,19183353188372473420096, 2052995326868420586298713, 234422512754956257129580893] |