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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 49 |
| 5 | 177 |
| 6 | 667 |
| 7 | 2543 |
| 8 | 10041 |
| 9 | 39539 |
| 10 | 158603 |
| 11 | 639927 |
| 12 | 2607159 |
| 13 | 10666927 |
| 14 | 43932533 |
| 15 | 181850695 |
| 16 | 755611295 |
| 17 | 3151697829 |
| 18 | 13194669577 |
| 19 | 55399106349 |
| 20 | 233230763877 |
| 21 | 984474496333 |
| 22 | 4165302588113 |
| 23 | 17658641745695 |
| 24 | 75013802642433 |
| 25 | 319243175216361 |
| 26 | 1360852049360291 |
| 27 | 5810001118731197 |
[1,1,5,13,49,177,667,2543,10041,39539,158603, 639927,2607159,10666927,43932533,181850695, 755611295,3151697829,13194669577,55399106349, 233230763877,984474496333,4165302588113, 17658641745695,75013802642433,319243175216361, 1360852049360291,5810001118731197] |