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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 5 |
| 3 | 10 |
| 4 | 25 |
| 5 | 77 |
| 6 | 280 |
| 7 | 1156 |
| 8 | 5267 |
| 9 | 25915 |
| 10 | 135214 |
| 11 | 736706 |
| 12 | 4139833 |
| 13 | 23767897 |
| 14 | 138468212 |
| 15 | 814675840 |
| 16 | 4824766303 |
| 17 | 28699128503 |
| 18 | 171207852154 |
| 19 | 1023332115838 |
| 20 | 6124430348357 |
| 21 | 36684624841813 |
| 22 | 219860794899520 |
| 23 | 1318179574171580 |
[3,5,10,25,77,280,1156,5267,25915,135214,736706, 4139833,23767897,138468212,814675840,4824766303, 28699128503,171207852154,1023332115838, 6124430348357,36684624841813,219860794899520, 1318179574171580] |