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 A155941 Numbers n such that 16*n+1 is not prime. 3
 0, 2, 3, 4, 5, 8, 9, 10, 11, 13, 14, 17, 18, 19, 20, 23, 24, 26, 29, 30, 31, 32, 33, 34, 35, 38, 39, 41, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 56, 57, 59, 60, 62, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 77, 79, 80, 82, 83, 84, 86, 87, 89, 90, 91, 92, 94, 95 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 EXAMPLE Distribution of a(n)>0 in the following triangular array: *; *,*; *,*,3; *,*,*,5; 2,*,*,*,*; *,4,*,*,*,*; *,*,*,*,*,*,14; *,*,*,*,*,*,*,18; *,*,*,*,13,*,*,*,*; *,*,*,*,*,17,*,*,*,*; *,*,10,*,*,*,*,*,*,*,33; *,*,*,14,*,*,*,*,*,*,*,39; 5,*,*,*,*,*,*,*,32,*,*,*,*; etc. where * marks the non-integer values of (2*h*k + k + h)/8 with h >= k >= 1. - Vincenzo Librandi, Jan 15 2013 MATHEMATICA Select[Range[0, 100], !PrimeQ[16 # + 1] &] (* Vincenzo Librandi, Oct 15 2012 *) PROG (MAGMA) [n: n in [0..100] |not IsPrime(16*n+1)]; // Vincenzo Librandi, Oct 15 2012 CROSSREFS Cf. A094407, A155942, A155943. Sequence in context: A031482 A047369 A004827 * A046892 A068406 A276878 Adjacent sequences:  A155938 A155939 A155940 * A155942 A155943 A155944 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Jan 31 2009 EXTENSIONS 0 added by Arkadiusz Wesolowski, Aug 03 2011 STATUS approved

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Last modified February 17 17:59 EST 2020. Contains 331999 sequences. (Running on oeis4.)