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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 13 |
| 7 | 25 |
| 8 | 45 |
| 9 | 91 |
| 10 | 175 |
| 11 | 322 |
| 12 | 645 |
| 13 | 1245 |
| 14 | 2325 |
| 15 | 4651 |
| 16 | 9031 |
| 17 | 17061 |
| 18 | 34123 |
| 19 | 66547 |
| 20 | 126763 |
| 21 | 253527 |
| 22 | 496063 |
| 23 | 950818 |
| 24 | 1901637 |
| 25 | 3730293 |
| 26 | 7184421 |
| 27 | 14368843 |
| 28 | 28243063 |
| 29 | 54604081 |
| 30 | 109208163 |
| 31 | 215008363 |
| 32 | 416990563 |
| 33 | 833981127 |
[0,0,1,3,6,13,25,45,91,175,322,645,1245,2325,4651, 9031,17061,34123,66547,126763,253527,496063, 950818,1901637,3730293,7184421,14368843,28243063, 54604081,109208163,215008363,416990563,833981127] |