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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 31 |
| 3 | 171 |
| 4 | 631 |
| 5 | 2059 |
| 6 | 6399 |
| 7 | 19483 |
| 8 | 58807 |
| 9 | 176859 |
| 10 | 531103 |
| 11 | 1593931 |
| 12 | 4782519 |
| 13 | 14348395 |
| 14 | 43046143 |
| 15 | 129139515 |
| 16 | 387419767 |
| 17 | 1162260667 |
| 18 | 3486783519 |
| 19 | 10460352235 |
| 20 | 31381058551 |
| 21 | 94143177675 |
| 22 | 282429535231 |
| 23 | 847288608091 |
| 24 | 2541865826871 |
[1,31,171,631,2059,6399,19483,58807,176859,531103, 1593931,4782519,14348395,43046143,129139515, 387419767,1162260667,3486783519,10460352235, 31381058551,94143177675,282429535231,847288608091, 2541865826871] |