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Williams prime MM 5
| Reserved! This sequence is currently reserved by: User:Karbon |
Definition
Primes of the form [math]\displaystyle{ 4 \cdot {5^n{-}1} }[/math].
Primes for n
1, 3, 9, 13, 15, 25, 39, 69, 165, 171, 209, 339, 2033, 6583, 15393, 282989
Search range
321000 (2018-12-07)
History
| Date | Remark |
|---|---|
| 2018-12-07 | Found n=282989, Karsten Bonath |
| 2007-20-12 | Checked to n=200000, Geoff Reynolds |
| 2007-07-13 | Checked to n=110000, Geoff Reynolds |
| 2006-08 | Found n=15393, antiroach |
| 1981 | Found n=1 ... 339, checked to n=500, H. C. Williams |
