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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 7 |
| 7 | 12 |
| 8 | 30 |
| 9 | 85 |
| 10 | 173 |
| 11 | 476 |
| 12 | 961 |
| 13 | 2652 |
| 14 | 8045 |
| 15 | 17637 |
| 16 | 51033 |
| 17 | 108950 |
| 18 | 312455 |
| 19 | 663535 |
| 20 | 1900470 |
| 21 | 5936673 |
| 22 | 13472296 |
| 23 | 39993895 |
| 24 | 87986917 |
| 25 | 257978502 |
| 26 | 820236724 |
| 27 | 1899474678 |
| 28 | 5723030586 |
| 29 | 12809477536 |
| 30 | 38036848410 |
| 31 | 84141805077 |
| 32 | 248369601964 |
[1,1,1,2,3,7,12,30,85,173,476,961,2652,8045,17637, 51033,108950,312455,663535,1900470,5936673, 13472296,39993895,87986917,257978502,820236724, 1899474678,5723030586,12809477536,38036848410, 84141805077,248369601964] |