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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 77 |
| 4 | 461 |
| 5 | 2621 |
| 6 | 14862 |
| 7 | 86295 |
| 8 | 520534 |
| 9 | 3285279 |
| 10 | 21751723 |
| 11 | 151075466 |
| 12 | 1099127680 |
| 13 | 8359344687 |
| 14 | 66315597630 |
| 15 | 547588531486 |
| 16 | 4697070887568 |
| 17 | 41777761715433 |
| 18 | 384670982322915 |
| 19 | 3661036657532939 |
| 20 | 35965773063598059 |
[1,11,77,461,2621,14862,86295,520534,3285279, 21751723,151075466,1099127680,8359344687, 66315597630,547588531486,4697070887568, 41777761715433,384670982322915,3661036657532939, 35965773063598059] |