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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 48 |
| 6 | 166 |
| 7 | 596 |
| 8 | 2221 |
| 9 | 8472 |
| 10 | 32995 |
| 11 | 130507 |
| 12 | 523100 |
| 13 | 2119454 |
| 14 | 8667529 |
| 15 | 35727261 |
| 16 | 148285069 |
| 17 | 619172847 |
| 18 | 2599212499 |
| 19 | 10963049307 |
| 20 | 46437309218 |
| 21 | 197454056586 |
| 22 | 842504023722 |
| 23 | 3606195947971 |
| 24 | 15480329150558 |
| 25 | 66628688247862 |
| 26 | 287475949517326 |
| 27 | 1243140817965661 |
[1,2,5,15,48,166,596,2221,8472,32995,130507, 523100,2119454,8667529,35727261,148285069, 619172847,2599212499,10963049307,46437309218, 197454056586,842504023722,3606195947971, 15480329150558,66628688247862,287475949517326, 1243140817965661] |