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 A153308 Numbers n such that 10*n+7 is not prime. 1
 2, 5, 7, 8, 11, 14, 17, 18, 20, 21, 23, 24, 26, 28, 29, 32, 35, 37, 38, 40, 41, 42, 43, 44, 47, 49, 50, 51, 52, 53, 56, 59, 62, 63, 65, 66, 68, 69, 70, 71, 73, 74, 76, 77, 80, 81, 83, 84, 86, 89, 91, 92, 95, 98, 100, 101, 102, 103, 104, 105, 106, 107 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 EXAMPLE Distribution of the terms in the following triangular array: *; *,*; *,*,*; 2,*,*,*; *,*,7,*,*; *,*,*,11,*,*; *,*,*,*,*,*,*; *,*,*,*,18,*,*,*; 5,*,*,*,*,24,*,*,*; *,*,14,*,*,*,*,35,*,*; *,*,*,20,*,*,*,*,43,*,*;etc. where * marks the non-integer values of (2*h*k + k + h - 3)/5 with h >= k >= 1. - Vincenzo Librandi, Jan 17 2013 MATHEMATICA Select[Range[0, 200], !PrimeQ[10*# + 7]&] (* Vincenzo Librandi, Jan 12 2013 *) PROG (MAGMA) [n: n in [0..150] | not IsPrime(10*n + 7)]; // Vincenzo Librandi, Jan 12 2013 CROSSREFS Sequence in context: A138671 A286693 A032724 * A216565 A285938 A192111 Adjacent sequences:  A153305 A153306 A153307 * A153309 A153310 A153311 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Dec 23 2008 STATUS approved

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Last modified November 19 03:53 EST 2017. Contains 294912 sequences.