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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 4 |
| 7 | 4 |
| 8 | 8 |
| 9 | 9 |
| 10 | 16 |
| 11 | 20 |
| 12 | 37 |
| 13 | 47 |
| 14 | 80 |
| 15 | 111 |
| 16 | 183 |
| 17 | 256 |
| 18 | 413 |
| 19 | 591 |
| 20 | 940 |
| 21 | 1373 |
| 22 | 2159 |
| 23 | 3214 |
| 24 | 5067 |
| 25 | 7649 |
| 26 | 12054 |
| 27 | 18488 |
| 28 | 29203 |
| 29 | 45237 |
| 30 | 71566 |
| 31 | 111658 |
| 32 | 176710 |
| 33 | 276870 |
| 34 | 437820 |
| 35 | 687354 |
| 36 | 1085577 |
| 37 | 1705080 |
| 38 | 2688285 |
| 39 | 4221333 |
| 40 | 6644088 |
| 41 | 10425748 |
[1,1,1,2,2,4,4,8,9,16,20,37,47,80,111,183,256,413, 591,940,1373,2159,3214,5067,7649,12054,18488, 29203,45237,71566,111658,176710,276870,437820, 687354,1085577,1705080,2688285,4221333,6644088, 10425748] |