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A153276 Numbers n >= 0 such that 5*n+6 is not prime. 1

%I

%S 0,2,3,4,6,8,9,10,12,14,15,16,17,18,20,21,22,23,24,26,27,28,30,31,32,

%T 33,34,36,38,39,40,42,43,44,45,46,48,50,51,52,54,56,57,58,59,60,62,63,

%U 64,66,67,68,69,70,71,72,73,74,75,76,77,78,80,81,82,84,86,87,88,89,90

%N Numbers n >= 0 such that 5*n+6 is not prime.

%C The odd terms are the integer values of (4*h*k + 2*k + 2*h - 5)/5, where h and k are positive integers. - _Vincenzo Librandi_, Jan 17 2013

%C The corresponding composite numbers are 6, 16, 21, 26, 36, 46, 51, 56, 66, 76, 81, 86, 91, 96, 106, 111, 116, 121, ... - _Michael B. Porter_, Jan 17 2013

%H Vincenzo Librandi, <a href="/A153276/b153276.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[0, 200], !PrimeQ[5 # + 6]&] (* _Vincenzo Librandi_, Jan 12 2013 *)

%o (MAGMA) [n: n in [0..150] | not IsPrime(5*n + 6)]; // _Vincenzo Librandi_, Jan 12 2013

%Y Cf. A081759.

%K nonn,easy

%O 1,2

%A _Vincenzo Librandi_, Dec 22 2008

%E Erroneous comment deleted by _N. J. A. Sloane_, Jun 23 2010

%E Corrected by _Jon E. Schoenfield_, Jun 24 2010

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Last modified May 15 07:17 EDT 2021. Contains 343909 sequences. (Running on oeis4.)