A243279 Numbers n such that (46^n - 1)/45 is prime.

2, 7, 19, 67, 211, 433, 2437, 2719, 19531

Offset

1,1

Comments

a(10) > 10^5.

Numbers corresponding to a(7)-a(9) are probable primes.

All terms are prime.

Links

Table of n, a(n) for n=1..9.

Harvey Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930.

Henri Lifchitz, Mersenne and Fermat primes field

Maple

A243279:=n->`if`(isprime((46^n - 1)/45), n, NULL); seq(A243279(n), n=1..100000); # Wesley Ivan Hurt, Apr 12 2014

Mathematica

Select[Prime[Range[100000]], PrimeQ[(46^# - 1)/45] &]

Prog

(PARI) is(n)=ispseudoprime((46^n-1)/45) \\ Charles R Greathouse IV, May 22 2017

Crossrefs

Cf. A028491, A004061, A004062, A004063, A004023, A005808, A004064, A016054, A006032, A006033, A006034, A006035, A127995, A127996, A127997, A127998, A127999, A098438, A128002, A128003, A128004, A128005, A240765, A242797.

Sequence in context: A083309 A318264 A164979 * A362097 A080873 A126162

Adjacent sequences: A243276 A243277 A243278 * A243280 A243281 A243282

Keyword

hard,more,nonn

Author

Robert Price, Jun 02 2014

Status

approved