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%I #14 Apr 13 2024 19:27:25
%S 12,13,15,17,20,21,24,26,28,29,30,31,34,36,38,39,42,43,45,47,50,51,54,
%T 56,58,59,62,63,65,67,70,71,74,76,78,79,82,83,85,87,92,93,95,97,1022,
%U 1023,1025,1027,1032,1033,1035,1037,1052,1053,1055,1057,1072,1073,1075
%N Numbers that have exactly as many prime digits as nonprime digits.
%t Select[Range[1200],Count[IntegerDigits[#],_?PrimeQ]== IntegerLength[#]/2&] (* _Harvey P. Dale_, Jun 02 2011 *)
%Y Cf. A085520.
%K base,easy,nonn
%O 1,1
%A _Jason Earls_, Jul 04 2003