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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 10 |
| 6 | 18 |
| 7 | 32 |
| 8 | 57 |
| 9 | 101 |
| 10 | 180 |
| 11 | 320 |
| 12 | 569 |
| 13 | 1012 |
| 14 | 1800 |
| 15 | 3201 |
| 16 | 5693 |
| 17 | 10125 |
| 18 | 18007 |
| 19 | 32025 |
| 20 | 56956 |
| 21 | 101295 |
| 22 | 180151 |
| 23 | 320395 |
| 24 | 569816 |
| 25 | 1013406 |
| 26 | 1802322 |
| 27 | 3205393 |
| 28 | 5700726 |
| 29 | 10138625 |
| 30 | 18031338 |
| 31 | 32068367 |
| 32 | 57032937 |
| 33 | 101431916 |
| 34 | 180394595 |
[1,1,2,3,6,10,18,32,57,101,180,320,569,1012,1800, 3201,5693,10125,18007,32025,56956,101295,180151, 320395,569816,1013406,1802322,3205393,5700726, 10138625,18031338,32068367,57032937,101431916, 180394595] |