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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 59 |
| 5 | 257 |
| 6 | 1088 |
| 7 | 4547 |
| 8 | 18906 |
| 9 | 78448 |
| 10 | 325210 |
| 11 | 1347552 |
| 12 | 5582415 |
| 13 | 23122986 |
| 14 | 95771842 |
| 15 | 396659584 |
| 16 | 1642825239 |
| 17 | 6803957409 |
| 18 | 28179306468 |
| 19 | 116707377067 |
| 20 | 483354745392 |
| 21 | 2001859113304 |
| 22 | 8290886288280 |
| 23 | 34337476313478 |
| 24 | 142211844759126 |
| 25 | 588983541662827 |
[1,3,13,59,257,1088,4547,18906,78448,325210, 1347552,5582415,23122986,95771842,396659584, 1642825239,6803957409,28179306468,116707377067, 483354745392,2001859113304,8290886288280, 34337476313478,142211844759126,588983541662827] |