| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 49 |
| 3 | 241 |
| 4 | 1171 |
| 5 | 5917 |
| 6 | 30067 |
| 7 | 151981 |
| 8 | 767377 |
| 9 | 3877045 |
| 10 | 19592047 |
| 11 | 98998267 |
| 12 | 500220187 |
| 13 | 2527540111 |
| 14 | 12771357967 |
| 15 | 64532102977 |
| 16 | 326072549563 |
| 17 | 1647603384079 |
| 18 | 8325132536305 |
| 19 | 42065847045655 |
| 20 | 212553428463613 |
| 21 | 1074005709153595 |
[7,49,241,1171,5917,30067,151981,767377,3877045, 19592047,98998267,500220187,2527540111, 12771357967,64532102977,326072549563, 1647603384079,8325132536305,42065847045655, 212553428463613,1074005709153595] |