

A128003


Numbers n such that (37^n  1)/36 is prime.


9



13, 71, 181, 251, 463, 521, 7321, 36473, 48157, 87421, 168527, 249341
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

7321 is a term found by Richard Fischer in 2004.  Alexander Adamchuk, Feb 11 2007
No other terms less than 100000.  Robert Price, Mar 18 2012


LINKS

Table of n, a(n) for n=1..12.
H. Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927930.
H. Lifchitz, Mersenne and Fermat primes field
Index to primes in various ranges, form ((k+1)^n1)/k


MATHEMATICA

Select[Prime[Range[100]], PrimeQ[(37^#1)/36]&]


PROG

(PARI) is(n)=ispseudoprime((37^n1)/36) \\ Charles R Greathouse IV, Feb 17 2017


CROSSREFS

Sequence in context: A340842 A253776 A158941 * A060103 A332943 A141989
Adjacent sequences: A128000 A128001 A128002 * A128004 A128005 A128006


KEYWORD

hard,more,nonn


AUTHOR

Alexander Adamchuk, Feb 11 2007


EXTENSIONS

a(7) from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008
a(8)a(10) from Robert Price, Mar 18 2012
a(11) from Paul Bourdelais, Aug 05 2019
a(12) from Paul Bourdelais, Aug 04 2020


STATUS

approved



