The Cunningham project aims at factoring bn + 1 and bn - 1, for b = 2, 3, 5, 6, 7, 10, 11, 12.
I once downloaded the database of this project and PIPS can now use some of these files to compute primitive polynomials more efficiently.
| b | bn + 1 | bn - 1 |
| 2 | 2+ | 2- |
| 3 | 3+ | 3- |
| 5 | 5+ | 5- |
| 6 | 6+ | 6- |
| 7 | 7+ | 7- |
| 10 | 10+ | 10- |
| 11 | 11+ | 11- |
| 12 | 12+ | 12- |