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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 4 |
| 5 | 6 |
| 6 | 12 |
| 7 | 20 |
| 8 | 33 |
| 9 | 61 |
| 10 | 109 |
| 11 | 191 |
| 12 | 349 |
| 13 | 639 |
| 14 | 1159 |
| 15 | 2133 |
| 16 | 3953 |
| 17 | 7311 |
| 18 | 13595 |
| 19 | 25417 |
| 20 | 47570 |
| 21 | 89272 |
| 22 | 168126 |
| 23 | 317226 |
| 24 | 599699 |
| 25 | 1136403 |
| 26 | 2157363 |
| 27 | 4102113 |
| 28 | 7813560 |
| 29 | 14906230 |
| 30 | 28476388 |
| 31 | 54475340 |
| 32 | 104347011 |
| 33 | 200113007 |
| 34 | 384207955 |
| 35 | 738468129 |
| 36 | 1420824404 |
| 37 | 2736345674 |
| 38 | 5274795212 |
[1,1,1,3,4,6,12,20,33,61,109,191,349,639,1159, 2133,3953,7311,13595,25417,47570,89272,168126, 317226,599699,1136403,2157363,4102113,7813560, 14906230,28476388,54475340,104347011,200113007, 384207955,738468129,1420824404,2736345674, 5274795212] |