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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 13 |
| 6 | 36 |
| 7 | 102 |
| 8 | 295 |
| 9 | 864 |
| 10 | 2557 |
| 11 | 7624 |
| 12 | 22868 |
| 13 | 68920 |
| 14 | 208527 |
| 15 | 632987 |
| 16 | 1926752 |
| 17 | 5878738 |
| 18 | 17973523 |
| 19 | 55050690 |
| 20 | 168881464 |
| 21 | 518818523 |
| 22 | 1595878573 |
| 23 | 4914522147 |
| 24 | 15150038699 |
| 25 | 46747391412 |
| 26 | 144370209690 |
| 27 | 446214862158 |
| 28 | 1380161749537 |
| 29 | 4271808447154 |
| 30 | 13230257155092 |
| 31 | 40999697820032 |
[1,1,2,5,13,36,102,295,864,2557,7624,22868,68920, 208527,632987,1926752,5878738,17973523,55050690, 168881464,518818523,1595878573,4914522147, 15150038699,46747391412,144370209690,446214862158, 1380161749537,4271808447154,13230257155092, 40999697820032] |