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%I #20 Sep 08 2022 08:45:39
%S 8,11,14,16,17,20,21,23,26,28,29,31,32,35,36,38,41,42,44,46,47,49,50,
%T 51,53,56,59,61,62,63,64,65,66,68,70,71,74,75,76,77,80,81,83,84,86,88,
%U 89,91,92,95,96,97,98,101,104,105,106,107,108,110,111,112
%N Numbers n such that 2*n-7 is composite.
%C Two more than the associated value in A153043, one more than in A153040.
%H Vincenzo Librandi, <a href="/A153039/b153039.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range[8,200], !PrimeQ[2*#-7]&] (* _Vladimir Joseph Stephan Orlovsky_, Feb 09 2012 *)
%o (Magma) [n: n in [5..220]| not IsPrime(2*n-7)]
%o (PARI) list(n)=apply(k->(k+7)/2,setminus(vector(n,k,2*k+7), primes(primepi(2*n+7)))) \\ _Charles R Greathouse IV_, May 14 2012
%Y Complement of A089192, A153040.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Dec 17 2008
%E Partially edited by _N. J. A. Sloane_, Jun 23 2010
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