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%I #10 Oct 16 2018 14:35:54
%S 0,1,2,3,5,6,7,9,10,12,14,15,17,20,21,22,24,27,28,29,34,35,36,37,38,
%T 40,43,47,48,49,51,55,56,57,58,59,62,64,66,68,69,70,71,73,76,79,82,83,
%U 86,89,90,93,94,98,105,108,110,111,112,114,115,119,120,121,122,124,126,127
%N Numbers n such that 30*n + 13 is prime.
%C Encoded primes with LSD 3, (SOD-1)/3 integer, (LSD, least significant digit; SOD, sum of digits). Divide any such number by 30, if the whole number portion of the quotient is in the sequence, the number is prime.
%F a(n) = (A132233(n) - 13)/30 = Floor[A132233(n)/30]. - Chandler
%e Example: 3163, with LSD 3 and (SOD-1)/3 = 4 (integer); Then 3163/30 = 105.433, or 105 which is in the sequence, thus 3163 is prime.
%t Select[Range[0,200],PrimeQ[30#+13]&] (* _Harvey P. Dale_, Oct 16 2018 *)
%o (PARI) is(n)=isprime(30*n+13) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A111175, A158573, A158614, A158648, A158791, A158806, A158850.
%K nonn
%O 1,3
%A _Ki Punches_, Mar 25 2009
%E Edited by _Ray Chandler_, Apr 07 2009
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