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| n | a(n) |
|---|---|
| 4 | 1 |
| 5 | 11 |
| 6 | 77 |
| 7 | 412 |
| 8 | 2009 |
| 9 | 8869 |
| 10 | 36988 |
| 11 | 146578 |
| 12 | 560498 |
| 13 | 2078927 |
| 14 | 7530385 |
| 15 | 26734692 |
| 16 | 93360884 |
| 17 | 321454484 |
| 18 | 1093599885 |
| 19 | 3681897625 |
| 20 | 12284317088 |
| 21 | 40660245162 |
| 22 | 133638662066 |
| 23 | 436488290069 |
| 24 | 1417680926923 |
| 25 | 4581355626106 |
[1,11,77,412,2009,8869,36988,146578,560498, 2078927,7530385,26734692,93360884,321454484, 1093599885,3681897625,12284317088,40660245162, 133638662066,436488290069,1417680926923, 4581355626106] |