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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 7 |
| 6 | 14 |
| 7 | 27 |
| 8 | 56 |
| 9 | 116 |
| 10 | 253 |
| 11 | 557 |
| 12 | 1272 |
| 13 | 2948 |
| 14 | 6998 |
| 15 | 16856 |
| 16 | 41306 |
| 17 | 102449 |
| 18 | 257294 |
| 19 | 652566 |
| 20 | 1670679 |
| 21 | 4311109 |
| 22 | 11206278 |
| 23 | 29316294 |
| 24 | 77144518 |
| 25 | 204072054 |
| 26 | 542446974 |
| 27 | 1448230644 |
| 28 | 3882179984 |
| 29 | 10445521740 |
| 30 | 28202158173 |
| 31 | 76387639678 |
[1,1,2,4,7,14,27,56,116,253,557,1272,2948,6998, 16856,41306,102449,257294,652566,1670679,4311109, 11206278,29316294,77144518,204072054,542446974, 1448230644,3882179984,10445521740,28202158173, 76387639678] |