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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 14 |
| 2 | 119 |
| 3 | 784 |
| 4 | 4396 |
| 5 | 22008 |
| 6 | 101220 |
| 7 | 435696 |
| 8 | 1777986 |
| 9 | 6943244 |
| 10 | 26129950 |
| 11 | 95282992 |
| 12 | 338108876 |
| 13 | 1171554776 |
| 14 | 3975215844 |
| 15 | 13239402960 |
| 16 | 43364985867 |
| 17 | 139925413866 |
| 18 | 445409413421 |
| 19 | 1400429394784 |
| 20 | 4353771487912 |
[1,14,119,784,4396,22008,101220,435696,1777986, 6943244,26129950,95282992,338108876,1171554776, 3975215844,13239402960,43364985867,139925413866, 445409413421,1400429394784,4353771487912] |