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%I #20 Sep 17 2019 11:15:27
%S 2,3,4,6,8,9,10,11,13,14,19,20,21,23,24,31,32,33,34,36,37,39,42,43,44,
%T 46,47,48,52,56,59,61,66,68,74,75,78,79,85,87,89,94,96,98,101,102,105,
%U 107,108,110,113,118,121,124,125,127,130,131,133,135,136,138
%N n such that the n-th centered 12-gonal number is prime. Indices of prime star numbers.
%C For n > 3, A003154(a(n)) = A057199(2*a(n)-2). - _Chai Wah Wu_, Sep 17 2019
%H Zak Seidov, <a href="/A184899/b184899.txt">Table of n, a(n) for n = 1..1000</a>
%F {n: 6*n^2 - 6*n + 1 is prime} = {n: A003154(n) is in A000040}.
%e 98 is in the sequence because 6*98^2 - 6*98 + 1 = 57037 is prime.
%t Select[Range[140],PrimeQ[6#^2-6#+1]&] (* _Harvey P. Dale_, Feb 16 2011 *)
%Y Cf. A083577, A000040, A003154, A057199.
%K nonn,easy
%O 1,1
%A _Jonathan Vos Post_, Feb 01 2011