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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 38 |
| 5 | 192 |
| 6 | 1156 |
| 7 | 8093 |
| 8 | 64749 |
| 9 | 582748 |
| 10 | 5827489 |
| 11 | 64102380 |
| 12 | 769228564 |
| 13 | 9999971337 |
| 14 | 139999598719 |
| 15 | 2099993980798 |
| 16 | 33599903692769 |
| 17 | 571198362777088 |
| 18 | 10281570529987586 |
| 19 | 195349840069764151 |
| 20 | 3906996801395283039 |
[1,3,9,38,192,1156,8093,64749,582748,5827489, 64102380,769228564,9999971337,139999598719, 2099993980798,33599903692769,571198362777088, 10281570529987586,195349840069764151, 3906996801395283039] |