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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 26 |
| 5 | 115 |
| 6 | 596 |
| 7 | 3623 |
| 8 | 25462 |
| 9 | 203939 |
| 10 | 1836032 |
| 11 | 18361831 |
| 12 | 201984098 |
| 13 | 2423820227 |
| 14 | 31509694204 |
| 15 | 441135811847 |
| 16 | 6617037458606 |
| 17 | 105872600222083 |
| 18 | 1799834206605272 |
| 19 | 32397015728269319 |
| 20 | 615543298868687962 |
[1,2,7,26,115,596,3623,25462,203939,1836032, 18361831,201984098,2423820227,31509694204, 441135811847,6617037458606,105872600222083, 1799834206605272,32397015728269319, 615543298868687962] |