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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 53 |
| 5 | 323 |
| 6 | 2359 |
| 7 | 19877 |
| 8 | 188591 |
| 9 | 1981963 |
| 10 | 22795849 |
| 11 | 284285351 |
| 12 | 3815293199 |
| 13 | 54762206985 |
| 14 | 836280215979 |
| 15 | 13527449608779 |
| 16 | 230894574439485 |
| 17 | 4144741143359355 |
| 18 | 78017419806432567 |
| 19 | 1535903379571939981 |
| 20 | 31550210953904250759 |
[1,3,11,53,323,2359,19877,188591,1981963,22795849, 284285351,3815293199,54762206985,836280215979, 13527449608779,230894574439485,4144741143359355, 78017419806432567,1535903379571939981, 31550210953904250759] |