|
|
A245237
|
|
Numbers n such that (48^n - 1)/47 is prime.
|
|
3
|
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
a(7) > 10^5.
All terms are prime.
|
|
LINKS
|
Table of n, a(n) for n=1..7.
Harvey Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930.
Henri Lifchitz, Mersenne and Fermat primes field
|
|
MAPLE
|
A245237:=n->`if`(isprime((48^n - 1)/47), n, NULL); seq(A245237(n), n=1..100000); # Wesley Ivan Hurt, Apr 12 2014
|
|
MATHEMATICA
|
Select[Prime[Range[100000]], PrimeQ[(48^# - 1)/47] &]
|
|
PROG
|
(PARI) is(n)=ispseudoprime((48^n-1)/47) \\ Charles R Greathouse IV, Jun 06 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, A243279.
Sequence in context: A016254 A016302 A253217 * A141942 A181043 A142899
Adjacent sequences: A245234 A245235 A245236 * A245238 A245239 A245240
|
|
KEYWORD
|
hard,more,nonn
|
|
AUTHOR
|
Robert Price, Jul 14 2014
|
|
EXTENSIONS
|
a(7) corresponds to a probable prime discovered by Paul Bourdelais, Aug 04 2020
|
|
STATUS
|
approved
|
|
|
|