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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 36 |
| 3 | 340 |
| 4 | 1914 |
| 5 | 13850 |
| 6 | 79266 |
| 7 | 523133 |
| 8 | 3016164 |
| 9 | 19260414 |
| 10 | 111909408 |
| 11 | 701498945 |
| 12 | 4101068118 |
| 13 | 25437014760 |
| 14 | 149386746096 |
| 15 | 920230171199 |
| 16 | 5422680704100 |
| 17 | 33245274102805 |
| 18 | 196418074534326 |
| 19 | 1200010201718666 |
| 20 | 7104314939065032 |
[6,36,340,1914,13850,79266,523133,3016164, 19260414,111909408,701498945,4101068118, 25437014760,149386746096,920230171199, 5422680704100,33245274102805,196418074534326, 1200010201718666,7104314939065032] |