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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 17 |
| 6 | 46 |
| 7 | 120 |
| 8 | 345 |
| 9 | 1022 |
| 10 | 2910 |
| 11 | 9040 |
| 12 | 27530 |
| 13 | 88493 |
| 14 | 283253 |
| 15 | 912384 |
| 16 | 3037696 |
| 17 | 9955390 |
| 18 | 33803098 |
| 19 | 113920402 |
| 20 | 390162517 |
| 21 | 1349732321 |
| 22 | 4642227231 |
| 23 | 16328414313 |
| 24 | 56978655042 |
| 25 | 202131478689 |
| 26 | 717829790091 |
| 27 | 2553299150122 |
| 28 | 9196541401438 |
| 29 | 32928272615601 |
| 30 | 119572300555189 |
| 31 | 433085570807293 |
| 32 | 1577395594151588 |
[1,1,2,3,8,17,46,120,345,1022,2910,9040,27530, 88493,283253,912384,3037696,9955390,33803098, 113920402,390162517,1349732321,4642227231, 16328414313,56978655042,202131478689,717829790091, 2553299150122,9196541401438,32928272615601, 119572300555189,433085570807293,1577395594151588] |