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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 7 |
| 6 | 12 |
| 7 | 29 |
| 8 | 56 |
| 9 | 134 |
| 10 | 283 |
| 11 | 672 |
| 12 | 1496 |
| 13 | 3568 |
| 14 | 8214 |
| 15 | 19678 |
| 16 | 46364 |
| 17 | 111766 |
| 18 | 267467 |
| 19 | 648941 |
| 20 | 1570540 |
| 21 | 3833777 |
| 22 | 9357181 |
| 23 | 22967808 |
| 24 | 56430230 |
| 25 | 139193762 |
| 26 | 343825265 |
| 27 | 851777363 |
| 28 | 2113382992 |
| 29 | 5255584309 |
| 30 | 13089273904 |
[1,1,2,3,7,12,29,56,134,283,672,1496,3568,8214, 19678,46364,111766,267467,648941,1570540,3833777, 9357181,22967808,56430230,139193762,343825265, 851777363,2113382992,5255584309,13089273904] |