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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 18 |
| 3 | 1701 |
| 4 | 278478 |
| 5 | 56542698 |
| 6 | 12838905972 |
| 7 | 3121895416077 |
| 8 | 795077021525526 |
| 9 | 209364566760439038 |
| 10 | 56540432581528153788 |
| 11 | 15573764062988183490786 |
| 12 | 4358381303784085630372620 |
| 13 | 1235729432868053981694246324 |
[1,1,18,1701,278478,56542698,12838905972, 3121895416077,795077021525526,209364566760439038, 56540432581528153788,15573764062988183490786, 4358381303784085630372620, 1235729432868053981694246324] |