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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 12 |
| 4 | 26 |
| 5 | 125 |
| 6 | 317 |
| 7 | 1642 |
| 8 | 4492 |
| 9 | 24188 |
| 10 | 69174 |
| 11 | 381613 |
| 12 | 1123923 |
| 13 | 6304781 |
| 14 | 18962485 |
| 15 | 107682542 |
| 16 | 329007674 |
| 17 | 1885923378 |
| 18 | 5833166568 |
| 19 | 33685017384 |
| 20 | 105214504816 |
| 21 | 611241171298 |
| 22 | 1924588709710 |
| 23 | 11236434464097 |
| 24 | 35617302886643 |
| 25 | 208815253200975 |
| 26 | 665665428686531 |
[1,2,3,12,26,125,317,1642,4492,24188,69174,381613, 1123923,6304781,18962485,107682542,329007674, 1885923378,5833166568,33685017384,105214504816, 611241171298,1924588709710,11236434464097, 35617302886643,208815253200975,665665428686531] |