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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 14 |
| 3 | 107 |
| 4 | 854 |
| 5 | 6997 |
| 6 | 58337 |
| 7 | 492459 |
| 8 | 4195910 |
| 9 | 36008585 |
| 10 | 310797519 |
| 11 | 2695146412 |
| 12 | 23462692889 |
| 13 | 204927930573 |
| 14 | 1794924637121 |
| 15 | 15759722754487 |
| 16 | 138667548834150 |
| 17 | 1222405694908165 |
| 18 | 10793913082306739 |
| 19 | 95452822514557693 |
| 20 | 845239550997448559 |
| 21 | 7493699336086875984 |
[1,2,14,107,854,6997,58337,492459,4195910, 36008585,310797519,2695146412,23462692889, 204927930573,1794924637121,15759722754487, 138667548834150,1222405694908165, 10793913082306739,95452822514557693, 845239550997448559,7493699336086875984] |