

A127998


Numbers n such that (24^n  1)/23 is prime.


10



3, 5, 19, 53, 71, 653, 661, 10343, 49307, 115597, 152783
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Note that 10343 was known to be a term of this sequence before 653 and 661.  Alonso del Arte, Mar 17 2014


LINKS

Table of n, a(n) for n=1..11.
H. Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927930.
Henri Lifchitz, Mersenne and Fermat primes field
Index to primes in various ranges, form ((k+1)^n1)/k


MATHEMATICA

Select[Prime[Range[100]], PrimeQ[(24^#  1)/23] &]


PROG

(PARI) isok(n) = isprime((24^n1)/23); \\ Michel Marcus, Mar 13 2016


CROSSREFS

Sequence in context: A209778 A148546 A148547 * A174132 A106918 A182357
Adjacent sequences: A127995 A127996 A127997 * A127999 A128000 A128001


KEYWORD

hard,more,nonn


AUTHOR

Alexander Adamchuk, Feb 11 2007


EXTENSIONS

a(6) and a(7) from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008
a(8) from Richard Fischer in 2004.
a(9) from Robert Price, Apr 18 2012
a(10) from Paul Bourdelais, Sep 12 2017
a(11) from Paul Bourdelais, Apr 09 2018


STATUS

approved



