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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 7 |
| 6 | 15 |
| 7 | 33 |
| 8 | 81 |
| 9 | 225 |
| 10 | 679 |
| 11 | 2139 |
| 12 | 6931 |
| 13 | 23185 |
| 14 | 80809 |
| 15 | 295141 |
| 16 | 1128487 |
| 17 | 4492363 |
| 18 | 18506923 |
| 19 | 78584193 |
| 20 | 343414489 |
| 21 | 1544535129 |
| 22 | 7151822771 |
| 23 | 34086446307 |
| 24 | 167058478355 |
| 25 | 840700482197 |
| 26 | 4337529697349 |
| 27 | 22915761303125 |
| 28 | 123863743341203 |
| 29 | 684588061704611 |
| 30 | 3867278506969535 |
[1,1,1,1,3,7,15,33,81,225,679,2139,6931,23185, 80809,295141,1128487,4492363,18506923,78584193, 343414489,1544535129,7151822771,34086446307, 167058478355,840700482197,4337529697349, 22915761303125,123863743341203,684588061704611, 3867278506969535] |