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| n | a(n) |
|---|---|
| 1 | 125 |
| 2 | 699 |
| 3 | 3355 |
| 4 | 15431 |
| 5 | 67595 |
| 6 | 287045 |
| 7 | 1188599 |
| 8 | 4827913 |
| 9 | 19308213 |
| 10 | 76254749 |
| 11 | 298049037 |
| 12 | 1154930779 |
| 13 | 4442888465 |
| 14 | 16986179207 |
| 15 | 64600876511 |
| 16 | 244577899139 |
| 17 | 922363567903 |
| 18 | 3466733140929 |
| 19 | 12991657380635 |
| 20 | 48562243341429 |
[125,699,3355,15431,67595,287045,1188599,4827913, 19308213,76254749,298049037,1154930779,4442888465, 16986179207,64600876511,244577899139,922363567903, 3466733140929,12991657380635,48562243341429] |