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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 51 |
| 3 | 323 |
| 4 | 2187 |
| 5 | 15435 |
| 6 | 111659 |
| 7 | 819243 |
| 8 | 6058155 |
| 9 | 44991659 |
| 10 | 334914219 |
| 11 | 2496201387 |
| 12 | 18617371307 |
| 13 | 138903833259 |
| 14 | 1036559854251 |
| 15 | 7736058194603 |
| 16 | 57739004914347 |
| 17 | 430954921634475 |
| 18 | 3216631813810859 |
| 19 | 24009028665518763 |
| 20 | 179204877435185835 |
[9,51,323,2187,15435,111659,819243,6058155, 44991659,334914219,2496201387,18617371307, 138903833259,1036559854251,7736058194603, 57739004914347,430954921634475,3216631813810859, 24009028665518763,179204877435185835] |