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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 13 |
| 5 | 173 |
| 6 | 3501 |
| 7 | 1420717 |
| 8 | 7343549869 |
| 9 | 24407739551034797 |
| 10 | 264579267653248177273154989 |
| 11 | 15107659029337673520218077770654501397966253 |
| 12 | 5900314832748922900613950065282124787723453785544193308390237364661677 |
[0,1,1,5,13,173,3501,1420717,7343549869, 24407739551034797,264579267653248177273154989, 15107659029337673520218077770654501397966253, 59003148327489229006139500652821247877234537855441\ 93308390237364661677] |