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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 19 |
| 3 | 172 |
| 4 | 1550 |
| 5 | 13951 |
| 6 | 125560 |
| 7 | 1130042 |
| 8 | 10170379 |
| 9 | 91533412 |
| 10 | 823800710 |
| 11 | 7414206391 |
| 12 | 66727857520 |
| 13 | 600550717682 |
| 14 | 5404956459139 |
| 15 | 48644608132252 |
| 16 | 437801473190270 |
| 17 | 3940213258712431 |
[2,19,172,1550,13951,125560,1130042,10170379, 91533412,823800710,7414206391,66727857520, 600550717682,5404956459139,48644608132252, 437801473190270,3940213258712431] |