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%I #19 Feb 04 2024 01:17:53
%S 11,12,13,15,16,18,19,21,24,25,28,30,31,33,36,39,40,43,45,46,49,51,54,
%T 58,60,61,63,64,66,73,75,78,79,84,85,88,91,93,96,99,100,105,106,108,
%U 109,115,121,123,124,126,129,130,135,138,141,144,145,148,150,151,156,163
%N Positive integers n such that 2n-19 is prime.
%H Harvey P. Dale, <a href="/A097932/b097932.txt">Table of n, a(n) for n = 1..1000</a>
%F Half of p+19 where p is a prime greater than 2.
%t (Prime[Range[2,100]]+19)/2 (* _Vladimir Joseph Stephan Orlovsky_, Feb 08 2010 *)
%t Select[Range[10,200],PrimeQ[2#-19]&] (* _Harvey P. Dale_, May 08 2017 *)
%Y Cf. A000040.
%Y Numbers n such that 2n+k is prime: A005097 (k=1), A067076 (k=3), A089038 (k=5), A105760 (k=7), A155722 (k=9), A101448 (k=11), A153081 (k=13), A089559 (k=15), A173059 (k=17), A153143 (k=19).
%Y Numbers n such that 2n-k is prime: A006254 (k=1), A098090 (k=3), A089253 (k=5), A089192 (k=7), A097069 (k=9), A097338 (k=11), A097363 (k=13), A097480 (k=15), A098605 (k=17), this sequence (k=19).
%K easy,nonn
%O 1,1
%A Douglas Winston (douglas.winston(AT)srupc.com), Sep 21 2004
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