

A002259


Numbers n such that 17*2^n+1 is prime.
(Formerly M2985 N1206)


2



3, 15, 27, 51, 147, 243, 267, 347, 471, 747, 2163, 3087, 5355, 6539, 7311, 99231, 824451, 1388355, 1990299
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


REFERENCES

H. Riesel, ``Prime numbers and computer methods for factorization,'' Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381384.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).


LINKS

Table of n, a(n) for n=1..19.
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
R. M. Robinson, A report on primes of the form k.2^n+1 and on factors of Fermat numbers, Proc. Amer. Math. Soc., 9 (1958), 673681.
Index entries for sequences of n such that k*2^n1 (or k*2^n+1) is prime


PROG

(PARI) is(n)=ispseudoprime(17*2^n+1) \\ Charles R Greathouse IV, Jun 06 2017


CROSSREFS

Sequence in context: A080065 A017557 A147041 * A050848 A077785 A222291
Adjacent sequences: A002256 A002257 A002258 * A002260 A002261 A002262


KEYWORD

hard,more,nonn


AUTHOR

N. J. A. Sloane.


EXTENSIONS

Added more terms (from http://web.archive.org/web/20161028080239/http://www.prothsearch.net/riesel.html), Joerg Arndt, Apr 07 2013


STATUS

approved



