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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 7 |
| 6 | 24 |
| 7 | 93 |
| 8 | 434 |
| 9 | 2110 |
| 10 | 11002 |
| 11 | 58713 |
| 12 | 321776 |
| 13 | 1792133 |
| 14 | 10131027 |
| 15 | 57949430 |
| 16 | 334970205 |
| 17 | 1953890318 |
| 18 | 11489753730 |
| 19 | 68054102361 |
| 20 | 405715557048 |
| 21 | 2433003221232 |
| 22 | 14668536954744 |
| 23 | 88869466378593 |
| 24 | 540834155878536 |
| 25 | 3304961537938269 |
| 26 | 20273202069859769 |
[1,1,1,3,7,24,93,434,2110,11002,58713,321776, 1792133,10131027,57949430,334970205,1953890318, 11489753730,68054102361,405715557048, 2433003221232,14668536954744,88869466378593, 540834155878536,3304961537938269, 20273202069859769] |