| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 31 |
| 4 | 287 |
| 5 | 3131 |
| 6 | 47527 |
| 7 | 823551 |
| 8 | 16843583 |
| 9 | 387440266 |
| 10 | 10009772937 |
| 11 | 285311670623 |
| 12 | 8918294639219 |
| 13 | 302875106592267 |
| 14 | 11112685050294387 |
| 15 | 437893920912795941 |
| 16 | 18447025553014982271 |
| 17 | 827240261886336764195 |
| 18 | 39346558271492953948522 |
| 19 | 1978419655660313589123999 |
[1,7,31,287,3131,47527,823551,16843583,387440266, 10009772937,285311670623,8918294639219, 302875106592267,11112685050294387, 437893920912795941,18447025553014982271, 827240261886336764195,39346558271492953948522, 1978419655660313589123999] |