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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, 498483, 504221
Search range
695000 (2019-01-17)
History
Date | Remark |
---|---|
2019-01-17 | Checked to n=695000, found n=498483 & 504221, Karsten Bonath |
2018-12-07 | Checked to n=321000, 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 | Checked to n=500, found n=1 ... 339, H. C. Williams |