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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 19 |
| 3 | 98 |
| 4 | 817 |
| 5 | 5567 |
| 6 | 41067 |
| 7 | 293058 |
| 8 | 2119375 |
| 9 | 15244204 |
| 10 | 109884658 |
| 11 | 791399401 |
| 12 | 5701648165 |
| 13 | 41072174493 |
| 14 | 295881007510 |
| 15 | 2131463579726 |
| 16 | 15354723297804 |
| 17 | 110612658781667 |
| 18 | 796834506416273 |
| 19 | 5740255973053614 |
| 20 | 41351802973320254 |
[1,19,98,817,5567,41067,293058,2119375,15244204, 109884658,791399401,5701648165,41072174493, 295881007510,2131463579726,15354723297804, 110612658781667,796834506416273,5740255973053614, 41351802973320254] |