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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 12 |
| 7 | 22 |
| 8 | 49 |
| 9 | 94 |
| 10 | 201 |
| 11 | 396 |
| 12 | 828 |
| 13 | 1656 |
| 14 | 3421 |
| 15 | 6899 |
| 16 | 14160 |
| 17 | 28686 |
| 18 | 58672 |
| 19 | 119156 |
| 20 | 243253 |
| 21 | 494688 |
| 22 | 1008860 |
| 23 | 2053168 |
| 24 | 4184892 |
| 25 | 8520248 |
| 26 | 17361293 |
| 27 | 35354517 |
| 28 | 72028485 |
| 29 | 146696143 |
| 30 | 298840769 |
| 31 | 608670551 |
| 32 | 1239888694 |
| 33 | 2525459305 |
[1,0,1,1,3,5,12,22,49,94,201,396,828,1656,3421, 6899,14160,28686,58672,119156,243253,494688, 1008860,2053168,4184892,8520248,17361293,35354517, 72028485,146696143,298840769,608670551,1239888694, 2525459305] |