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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 12 |
| 5 | 23 |
| 6 | 44 |
| 7 | 84 |
| 8 | 158 |
| 9 | 297 |
| 10 | 561 |
| 11 | 1056 |
| 12 | 1989 |
| 13 | 3746 |
| 14 | 7056 |
| 15 | 13287 |
| 16 | 25023 |
| 17 | 47125 |
| 18 | 88746 |
| 19 | 167127 |
| 20 | 314735 |
| 21 | 592710 |
| 22 | 1116193 |
| 23 | 2102019 |
| 24 | 3958531 |
| 25 | 7454720 |
| 26 | 14038755 |
| 27 | 26437833 |
| 28 | 49787820 |
| 29 | 93760597 |
| 30 | 176570285 |
| 31 | 332517781 |
| 32 | 626198652 |
| 33 | 1179259497 |
[1,1,3,6,12,23,44,84,158,297,561,1056,1989,3746, 7056,13287,25023,47125,88746,167127,314735,592710, 1116193,2102019,3958531,7454720,14038755,26437833, 49787820,93760597,176570285,332517781,626198652, 1179259497] |