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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 19 |
| 3 | 413 |
| 4 | 6997 |
| 5 | 84910 |
| 6 | 762227 |
| 7 | 5385305 |
| 8 | 31454256 |
| 9 | 157376166 |
| 10 | 692347393 |
| 11 | 2731553014 |
| 12 | 9814551889 |
| 13 | 32510650689 |
| 14 | 100275435009 |
| 15 | 290361386801 |
| 16 | 794754882094 |
| 17 | 2068183070502 |
| 18 | 5142171510385 |
| 19 | 12267196687798 |
| 20 | 28182388823719 |
[1,19,413,6997,84910,762227,5385305,31454256, 157376166,692347393,2731553014,9814551889, 32510650689,100275435009,290361386801, 794754882094,2068183070502,5142171510385, 12267196687798,28182388823719] |