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%I #18 Feb 03 2024 00:54:47
%S 2,7,11,17,29,41,59,71,79,97,127,137,139,149,151,181,197,199,241,251,
%T 277,281,307,337,347,367,379,401,431,479,491,541,569,587,659,701,709,
%U 757,797,809,821,827,829,857,877,881,947,991,1021,1051,1109,1117,1129,1151,1229
%N Primes p such that 18*p+1 is also a prime.
%H Vincenzo Librandi, <a href="/A165810/b165810.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = (A165811(n)-1)/18.
%e For p=2, 18*p+1=37. For p=7, 18*p+1=127. For p=11, 18*p+1=199.
%t Select[Prime[Range[1000]],PrimeQ[18#+1]&] (* _Harvey P. Dale_, Mar 06 2011 *)
%Y Cf. A111094, A153400, A165811.
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Sep 28 2009
%E Extended by _R. J. Mathar_, Oct 16 2009
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