A273517 Numbers k such that 2*14^k-1 is prime.

4, 10, 124, 550, 4720, 14644, 23896, 83384, 95492

Offset: 1

Author

Jack P. Eisenmann, May 23 2016

Keywords

• nonn
• more

Comments

a(10) > 10^5. - Tyler NeSmith, May 11 2021

Links

• J. Brillhart, D. H. Lehmer and J. L. Selfridge, New primality criteria and factorizations of 2^m+-1, Math. Compl. 29 (1975) 620-647.
• John Eisenmann, Prime Numbers of the Form a * 14^b - 1.
• Victor Shoup, A Computational Introduction to Number Theory and Algebra, 2008, page 348.
• Eric Weisstein's World of Mathematics, Lucas Sequence.
• Eric Weisstein's World of Mathematics, Rabin-Miller Strong Pseudoprime Test.

Programs

Mathematica

Select[Range[0, 15000], PrimeQ[2 14^# - 1] &] (* Vincenzo Librandi, May 24 2016 *)

PARI

is(n)=ispseudoprime(2*14^n-1) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

a(7)-a(9) from Tyler NeSmith, May 11 2021