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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 41 |
| 5 | 406 |
| 6 | 7127 |
| 7 | 235147 |
| 8 | 15191966 |
| 9 | 1953128401 |
| 10 | 501361942127 |
| 11 | 257110692345262 |
| 12 | 263513099974512041 |
| 13 | 539923433830720468321 |
| 14 | 2212048542930121133510402 |
| 15 | 18123271334339868892408048927 |
[1,1,2,7,41,406,7127,235147,15191966,1953128401, 501361942127,257110692345262,263513099974512041, 539923433830720468321,2212048542930121133510402, 18123271334339868892408048927] |