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| n | a(n) |
|---|---|
| 1 | 17 |
| 2 | 51 |
| 3 | 161 |
| 4 | 531 |
| 5 | 1817 |
| 6 | 6411 |
| 7 | 23201 |
| 8 | 85731 |
| 9 | 322217 |
| 10 | 1227771 |
| 11 | 4729841 |
| 12 | 18379731 |
| 13 | 71908217 |
| 14 | 282817131 |
| 15 | 1116854081 |
| 16 | 4424238531 |
| 17 | 17567551817 |
| 18 | 69882262491 |
| 19 | 278365739921 |
| 20 | 1109974078131 |
| 21 | 4429431765017 |
| 22 | 17686337611851 |
| 23 | 70651190491361 |
| 24 | 282322298874531 |
[17,51,161,531,1817,6411,23201,85731,322217, 1227771,4729841,18379731,71908217,282817131, 1116854081,4424238531,17567551817,69882262491, 278365739921,1109974078131,4429431765017, 17686337611851,70651190491361,282322298874531] |