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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 7 |
| 7 | 16 |
| 8 | 39 |
| 9 | 93 |
| 10 | 246 |
| 11 | 671 |
| 12 | 1884 |
| 13 | 5578 |
| 14 | 16887 |
| 15 | 52854 |
| 16 | 170649 |
| 17 | 563703 |
| 18 | 1914366 |
| 19 | 6649798 |
| 20 | 23610987 |
| 21 | 85689987 |
| 22 | 317054427 |
| 23 | 1196183592 |
| 24 | 4595744763 |
| 25 | 17965311672 |
| 26 | 71426213637 |
| 27 | 288535755417 |
| 28 | 1183807706841 |
| 29 | 4929801601890 |
| 30 | 20825803784129 |
| 31 | 89210585925338 |
[1,1,1,1,2,4,7,16,39,93,246,671,1884,5578,16887, 52854,170649,563703,1914366,6649798,23610987, 85689987,317054427,1196183592,4595744763, 17965311672,71426213637,288535755417, 1183807706841,4929801601890,20825803784129, 89210585925338] |