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 A058592 Numbers k such that 7*2^k + 3 is prime. 1
 1, 2, 3, 5, 13, 14, 21, 30, 50, 363, 391, 1418, 2541, 2803, 7334, 10229, 12078, 14034, 15949, 22878, 25554, 31554, 41739 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(24) > 44043. - Jinyuan Wang, Jan 20 2020 LINKS MATHEMATICA Do[ If[ PrimeQ[ 7*2^n + 3 ], Print[ n ] ], {n, 5000} ] Select[Range[10000], PrimeQ[7*2^# + 3] &] (* Vincenzo Librandi, Oct 03 2012 *) PROG (PARI) is(n)=ispseudoprime(7*2^n+3) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Cf. A058593 (7*2^k - 3 is prime). Sequence in context: A264745 A251414 A145343 * A268509 A260594 A228940 Adjacent sequences:  A058589 A058590 A058591 * A058593 A058594 A058595 KEYWORD nonn,more AUTHOR Robert G. Wilson v, Dec 26 2000 EXTENSIONS a(15) from Vincenzo Librandi, Oct 03 2012 a(16)-a(23) from Jinyuan Wang, Jan 20 2020 STATUS approved

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Last modified May 10 21:08 EDT 2021. Contains 343780 sequences. (Running on oeis4.)