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Williams prime MM 5

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Definition

Primes of the form [math]\displaystyle{ 4 \cdot {5^n{-}1} }[/math], n ≥ 1.

Primes for n

1, 3, 9, 13, 15, 25, 39, 69, 165, 171, 209, 339, 2033, 6583, 15393, 282989, 498483, 504221, 754611

Search range

765000 (2019-01-30)

History

Date Remark
2019-01-27 found n = 754611, Karsten Bonath
2018-12-24 found n = 504221, Karsten Bonath
2018-12-23 found n = 498483, Karsten Bonath
2018-12-06 Checked to n = 1 - 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

See also

External links