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| n | a(n) |
|---|---|
| 1 | 25 |
| 2 | 63 |
| 3 | 149 |
| 4 | 357 |
| 5 | 829 |
| 6 | 1941 |
| 7 | 4479 |
| 8 | 10413 |
| 9 | 24087 |
| 10 | 56079 |
| 11 | 130523 |
| 12 | 305431 |
| 13 | 715961 |
| 14 | 1685595 |
| 15 | 3977689 |
| 16 | 9418701 |
| 17 | 22352933 |
| 18 | 53188057 |
| 19 | 126803131 |
| 20 | 302898825 |
| 21 | 724648975 |
| 22 | 1736139523 |
| 23 | 4164319291 |
| 24 | 9999028263 |
| 25 | 24029343133 |
| 26 | 57789827919 |
| 27 | 139068433021 |
[25,63,149,357,829,1941,4479,10413,24087,56079, 130523,305431,715961,1685595,3977689,9418701, 22352933,53188057,126803131,302898825,724648975, 1736139523,4164319291,9999028263,24029343133, 57789827919,139068433021] |