A032412 - OEIS

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A032412

Numbers k such that 125*2^k+1 is prime.

1, 5, 7, 17, 25, 35, 67, 281, 331, 491, 581, 941, 1205, 1279, 1411, 1631, 1895, 2735, 3475, 13955, 50491, 68819, 423155, 432719, 507637, 701981, 924085, 1107425, 2071555, 2369461

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..30.

Ray Ballinger, Proth Search Page

Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300

Y. Gallot, Proth.exe: Windows Program for Finding Large Primes

Wilfrid Keller, List of primes k.2^n - 1 for k < 300

Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime

MATHEMATICA

Select[Range[1000], PrimeQ[125*2^# + 1] & ] (* Robert Price, Dec 17 2018 *)