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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 65 |
| 3 | 363 |
| 4 | 2610 |
| 5 | 19187 |
| 6 | 134123 |
| 7 | 956810 |
| 8 | 6834267 |
| 9 | 48617437 |
| 10 | 346450092 |
| 11 | 2468975717 |
| 12 | 17589178379 |
| 13 | 125325570606 |
| 14 | 892966071949 |
| 15 | 6362349116511 |
| 16 | 45332105458684 |
| 17 | 322993886339549 |
| 18 | 2301344223018433 |
| 19 | 16397188735256084 |
| 20 | 116830761042732185 |
[6,65,363,2610,19187,134123,956810,6834267, 48617437,346450092,2468975717,17589178379, 125325570606,892966071949,6362349116511, 45332105458684,322993886339549,2301344223018433, 16397188735256084,116830761042732185] |