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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 27 |
| 3 | 204 |
| 4 | 1941 |
| 5 | 19572 |
| 6 | 198567 |
| 7 | 1999056 |
| 8 | 19931337 |
| 9 | 196939572 |
| 10 | 1930784091 |
| 11 | 18802964760 |
| 12 | 182062831005 |
| 13 | 1754100012108 |
| 14 | 16826739416271 |
| 15 | 160799296563312 |
| 16 | 1531421717572401 |
| 17 | 14540848734272388 |
| 18 | 137690120683444995 |
| 19 | 1300613432805623496 |
| 20 | 12258142039717884549 |
[6,27,204,1941,19572,198567,1999056,19931337, 196939572,1930784091,18802964760,182062831005, 1754100012108,16826739416271,160799296563312, 1531421717572401,14540848734272388, 137690120683444995,1300613432805623496, 12258142039717884549] |