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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 8 |
| 7 | 17 |
| 8 | 40 |
| 9 | 104 |
| 10 | 291 |
| 11 | 857 |
| 12 | 2634 |
| 13 | 8455 |
| 14 | 28424 |
| 15 | 100117 |
| 16 | 368465 |
| 17 | 1410903 |
| 18 | 5599073 |
| 19 | 22968514 |
| 20 | 97267342 |
| 21 | 424927846 |
| 22 | 1913764155 |
| 23 | 8877181958 |
| 24 | 42358589064 |
| 25 | 207639979365 |
| 26 | 1044360973987 |
| 27 | 5384167878948 |
| 28 | 28429186870051 |
| 29 | 153638182314504 |
| 30 | 849295001319211 |
[1,1,1,1,2,4,8,17,40,104,291,857,2634,8455,28424, 100117,368465,1410903,5599073,22968514,97267342, 424927846,1913764155,8877181958,42358589064, 207639979365,1044360973987,5384167878948, 28429186870051,153638182314504,849295001319211] |