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%I #26 Sep 08 2022 08:45:39
%S 10,14,17,20,22,23,26,27,29,32,34,35,37,38,41,42,44,47,48,50,52,53,55,
%T 56,57,59,62,65,67,68,69,70,71,72,74,76,77,80,81,82,83,86,87,89,90,92,
%U 94,95,97,98,101,102,103,104
%N Numbers n >=10 such that 2*n-19 is not a prime.
%C One more than associated values in A153051, two more than A153047. - _R. J. Mathar_, Jan 05 2011
%C The terms after a(1) are the values of 2*h*k + k + h + 10, where h and k are positive integers.- _Vincenzo Librandi_, Jan 19 2013
%H Vincenzo Librandi, <a href="/A153041/b153041.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[10, 200], !PrimeQ[2 # - 19] &] (* _Vincenzo Librandi_, Jan 19 2013 *)
%o (Magma) [n: n in [10..150] | not IsPrime(2*n - 19)]; // _Vincenzo Librandi_, Jan 19 2013
%Y Cf. A097932, A155704.
%Y Numbers n such that 2n-k is not prime: A104275 (k=1), A153043 (k=3), A153040 (k=5), A153039 (k=7), A153044 (k=9), A153045 (k=11), A153049 (k=13), A153047 (k=15), A153051 (k=17), A153041 (k=19).
%Y Similar sequence listed also in A089559, A153144.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Dec 17 2008
%E Edited by _N. J. A. Sloane_, Jun 22 2010
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