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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 40 |
| 4 | 273 |
| 5 | 2727 |
| 6 | 41520 |
| 7 | 944307 |
| 8 | 32403123 |
| 9 | 1667310336 |
| 10 | 129124175985 |
| 11 | 15018894671481 |
| 12 | 2626862719652352 |
| 13 | 690390044069042835 |
| 14 | 272767004386769371833 |
| 15 | 161965593156881121867648 |
[3,9,40,273,2727,41520,944307,32403123,1667310336, 129124175985,15018894671481,2626862719652352, 690390044069042835,272767004386769371833, 161965593156881121867648] |