%I #12 Jul 28 2021 04:25:13

%S 0,2,6,9,11,15,23,27,30,32,33,39,41,44,48,50,56,57,62,65,68,69,74,78,

%T 81,84,90,92,95,104,113,119,120,126,128,134,138,141,147,150,156,159,

%U 161,167,168,171,180,185,189,191,197,210,215,216,218,222,225,231

%N Numbers k such that k prefixed by '5' and followed by '3' is prime.

%t Select[Range[0,250],PrimeQ[FromDigits[Join[{5},IntegerDigits[#],{3}]]]&] (* _Harvey P. Dale_, Mar 28 2013 *)

%K nonn,base

%O 1,2

%A _Patrick De Geest_, May 15 1998