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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 7 |
| 5 | 12 |
| 6 | 21 |
| 7 | 39 |
| 8 | 69 |
| 9 | 130 |
| 10 | 240 |
| 11 | 451 |
| 12 | 854 |
| 13 | 1620 |
| 14 | 3101 |
| 15 | 5941 |
| 16 | 11443 |
| 17 | 22080 |
| 18 | 42724 |
| 19 | 82835 |
| 20 | 160914 |
| 21 | 313149 |
| 22 | 610230 |
| 23 | 1190802 |
| 24 | 2326448 |
| 25 | 4550161 |
| 26 | 8908095 |
| 27 | 17455391 |
| 28 | 34232368 |
| 29 | 67184426 |
| 30 | 131949378 |
| 31 | 259313689 |
| 32 | 509925468 |
| 33 | 1003302084 |
[1,1,2,4,7,12,21,39,69,130,240,451,854,1620,3101, 5941,11443,22080,42724,82835,160914,313149,610230, 1190802,2326448,4550161,8908095,17455391,34232368, 67184426,131949378,259313689,509925468,1003302084] |