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 A153381 Numbers n such that 11*n+5 is not prime. 1
 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 33, 35, 37, 38, 39, 40, 41, 43, 44, 45, 46, 47, 48, 49, 50, 51, 53, 55, 56, 57, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 79, 80, 81, 83, 85, 86, 87, 88 (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 the even terms in the following triangular array: *; *,*; *,*,4; 2,*,*,*; *,*,*,*,*; *,*,*,*,*,*; *,*,*,*,*,*,20; *,*,*,*,*,*,*,*,; *,*,*,*,*,22,*,*,*; *,*,*,*,*,*,*,32,*,*; *,10,*,*,*,*,*,*,*,*,*; *,*,*,20,*,*,*,*,*,*,*,*; *,*,*,*,*,*,*,*,*,*,56,*,*: *,*,18,*,*,*,*,*,*,*,*,*,*,76; 8,*,*,*,*,*,*,*,*,*,*,70,*,*,*; etc. where * marks the non-integer values of (4*h*k + 2*k + 2*h - 4)/11 with h >= k >= 1. - Vincenzo Librandi, Jan 17 2013 MATHEMATICA Select[Range[0, 200], !PrimeQ[11 # + 5] &] (* Vincenzo Librandi, Jan 13 2013 *) PROG (MAGMA) [n: n in [0..150] | not IsPrime(11*n+5)]; // Vincenzo Librandi, Jan 13 2013 CROSSREFS Cf. A108233. Sequence in context: A098901 A098767 A333559 * A307750 A319630 A324849 Adjacent sequences:  A153378 A153379 A153380 * A153382 A153383 A153384 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Dec 25 2008 EXTENSIONS Erroneous comment deleted by N. J. A. Sloane, Jun 23 2010 STATUS approved

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Last modified September 28 02:39 EDT 2020. Contains 337392 sequences. (Running on oeis4.)