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 A002242 Numbers n such that 45*2^n-1 is prime. (Formerly M0502 N0181) 0
 1, 2, 3, 4, 5, 6, 8, 9, 14, 15, 16, 22, 28, 29, 36, 37, 54, 59, 85, 93, 117, 119, 161, 189, 193, 256, 308, 322, 327, 411, 466, 577, 591, 902, 928, 946, 1162, 1428, 1708, 1724, 2063, 2922, 2951, 3111, 3402, 4024, 4485, 5859, 6124, 8981, 10628, 19283, 23522, 26591, 28914, 33954, 34743, 76367, 103546, 103912, 104452, 125132, 139883, 174102, 249065, 306394, 368553, 528245, 645542, 818648 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 REFERENCES H. Riesel, Lucasian criteria for the primality of N=h.2^n-1, Math. Comp., 23 (1969), 869-875. 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 Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300 Wilfrid Keller, List of primes k.2^n - 1 for k < 300 Kosmaj, Riesel list k<300. PROG (PARI) v=[ ]; for(n=1, 2000, if(isprime(45*2^n-1), v=concat(v, n), )); v CROSSREFS Sequence in context: A121644 A259623 A305734 * A317676 A039125 A203616 Adjacent sequences:  A002239 A002240 A002241 * A002243 A002244 A002245 KEYWORD hard,nonn AUTHOR EXTENSIONS More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008 STATUS approved

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Last modified April 23 05:34 EDT 2021. Contains 343199 sequences. (Running on oeis4.)