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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 17 |
| 4 | 119 |
| 5 | 929 |
| 6 | 7755 |
| 7 | 67745 |
| 8 | 611567 |
| 9 | 5660033 |
| 10 | 53415251 |
| 11 | 512072241 |
| 12 | 4972855783 |
| 13 | 48817414177 |
| 14 | 483649249179 |
| 15 | 4829637141825 |
| 16 | 48559914920927 |
| 17 | 491195889610241 |
| 18 | 4995080271452067 |
| 19 | 51037379418765905 |
| 20 | 523695644006188887 |
| 21 | 5394266374440159649 |
| 22 | 55756104288043890667 |
[1,3,17,119,929,7755,67745,611567,5660033, 53415251,512072241,4972855783,48817414177, 483649249179,4829637141825,48559914920927, 491195889610241,4995080271452067, 51037379418765905,523695644006188887, 5394266374440159649,55756104288043890667] |