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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 5 |
| 3 | 26 |
| 4 | 123 |
| 5 | 633 |
| 6 | 3428 |
| 7 | 18899 |
| 8 | 106599 |
| 9 | 618585 |
| 10 | 3674665 |
| 11 | 22190640 |
| 12 | 135570897 |
| 13 | 835884024 |
| 14 | 5196879659 |
| 15 | 32568136350 |
| 16 | 205609418532 |
| 17 | 1306436325774 |
| 18 | 8346088687406 |
| 19 | 53563228719519 |
| 20 | 345155128538327 |
| 21 | 2232566289999786 |
[6,5,26,123,633,3428,18899,106599,618585,3674665, 22190640,135570897,835884024,5196879659, 32568136350,205609418532,1306436325774, 8346088687406,53563228719519,345155128538327, 2232566289999786] |