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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 26 |
| 4 | 31 |
| 5 | 57 |
| 6 | 373 |
| 7 | 430 |
| 8 | 2093 |
| 9 | 2523 |
| 10 | 17231 |
| 11 | 19754 |
| 12 | 36985 |
| 13 | 204679 |
| 14 | 855701 |
| 15 | 1060380 |
| 16 | 53874701 |
| 17 | 54935081 |
| 18 | 273615025 |
| 19 | 1423010206 |
| 20 | 1696625231 |
| 21 | 3119635437 |
| 22 | 20414437853 |
| 23 | 23534073290 |
| 24 | 114550731013 |
| 25 | 138084804303 |
| 26 | 943059556831 |
| 27 | 1081144361134 |
| 28 | 2024203917965 |
[1,1,5,26,31,57,373,430,2093,2523,17231,19754, 36985,204679,855701,1060380,53874701,54935081, 273615025,1423010206,1696625231,3119635437, 20414437853,23534073290,114550731013,138084804303, 943059556831,1081144361134,2024203917965] |