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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 15 |
| 4 | 49 |
| 5 | 165 |
| 6 | 584 |
| 7 | 2134 |
| 8 | 7930 |
| 9 | 30004 |
| 10 | 115286 |
| 11 | 448041 |
| 12 | 1758361 |
| 13 | 6960484 |
| 14 | 27766468 |
| 15 | 111490323 |
| 16 | 450177914 |
| 17 | 1827430423 |
| 18 | 7453136569 |
| 19 | 30521419571 |
| 20 | 125469410644 |
| 21 | 517600974331 |
| 22 | 2141983544608 |
| 23 | 8890103668822 |
| 24 | 36997531250241 |
| 25 | 154355482106971 |
| 26 | 645473861118404 |
| 27 | 2705027636972910 |
[1,2,5,15,49,165,584,2134,7930,30004,115286, 448041,1758361,6960484,27766468,111490323, 450177914,1827430423,7453136569,30521419571, 125469410644,517600974331,2141983544608, 8890103668822,36997531250241,154355482106971, 645473861118404,2705027636972910] |