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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 14 |
| 7 | 26 |
| 8 | 47 |
| 9 | 85 |
| 10 | 158 |
| 11 | 295 |
| 12 | 552 |
| 13 | 1048 |
| 14 | 2000 |
| 15 | 3829 |
| 16 | 7373 |
| 17 | 14216 |
| 18 | 27505 |
| 19 | 53378 |
| 20 | 103728 |
| 21 | 201981 |
| 22 | 393900 |
| 23 | 769192 |
| 24 | 1503947 |
| 25 | 2943906 |
| 26 | 5767973 |
| 27 | 11311511 |
| 28 | 22200845 |
| 29 | 43605974 |
| 30 | 85707102 |
| 31 | 168564864 |
| 32 | 331720141 |
| 33 | 653151962 |
| 34 | 1286702079 |
[1,1,2,2,4,9,14,26,47,85,158,295,552,1048,2000, 3829,7373,14216,27505,53378,103728,201981,393900, 769192,1503947,2943906,5767973,11311511,22200845, 43605974,85707102,168564864,331720141,653151962, 1286702079] |