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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 61 |
| 4 | 281 |
| 5 | 1261 |
| 6 | 5545 |
| 7 | 24025 |
| 8 | 102961 |
| 9 | 437581 |
| 10 | 1847561 |
| 11 | 7759753 |
| 12 | 32449873 |
| 13 | 135207801 |
| 14 | 561632401 |
| 15 | 2326762801 |
| 16 | 9617286241 |
| 17 | 39671305741 |
| 18 | 163352435401 |
| 19 | 671560012201 |
| 20 | 2756930576401 |
| 21 | 11303415363241 |
| 22 | 46290177201841 |
| 23 | 189368906734801 |
| 24 | 773942488394401 |
[1,3,13,61,281,1261,5545,24025,102961,437581, 1847561,7759753,32449873,135207801,561632401, 2326762801,9617286241,39671305741,163352435401, 671560012201,2756930576401,11303415363241, 46290177201841,189368906734801,773942488394401] |