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 A002256 Numbers n such that 9*2^n+1 is prime. (Formerly M0751 N0283) 4
 1, 2, 3, 6, 7, 11, 14, 17, 33, 42, 43, 63, 65, 67, 81, 134, 162, 206, 211, 366, 663, 782, 1305, 1411, 1494, 2297, 2826, 3230, 3354, 3417, 3690, 4842, 5802, 6937, 7967, 9431, 13903, 22603, 24422, 39186, 43963, 47003, 49902, 67943, 114854, 127003, 145247 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 REFERENCES H. Riesel, ``Prime numbers and computer methods for factorization,'' Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381-384. 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 Jeppe Stig Nielsen, Table of n, a(n) for n = 1..60 Ray Ballinger, Proth Search Page Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300 C. K. Caldwell, The Prime Pages 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), 673-681. Eric Weisstein's World of Mathematics, Proth Prime MATHEMATICA Select[Range[2019], PrimeQ[9*2^#+1]&] (* Metin Sariyar, Sep 21 2019 *) CROSSREFS Cf. A050528. Sequence in context: A171033 A269983 A323066 * A230584 A294176 A008765 Adjacent sequences:  A002253 A002254 A002255 * A002257 A002258 A002259 KEYWORD nonn AUTHOR EXTENSIONS a(48) from Arkadiusz Wesolowski, Oct 22 2011 Added more terms (from http://web.archive.org/web/20161028080239/http://www.prothsearch.net/riesel.html), Joerg Arndt, Apr 07 2013 Terms moved from Data to b-file, and more terms put in b-file, by Jeppe Stig Nielsen, Sep 21 2019 STATUS approved

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Last modified February 24 08:13 EST 2020. Contains 332201 sequences. (Running on oeis4.)