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A085556
Numbers that have exactly as many prime digits as nonprime digits.
1
12, 13, 15, 17, 20, 21, 24, 26, 28, 29, 30, 31, 34, 36, 38, 39, 42, 43, 45, 47, 50, 51, 54, 56, 58, 59, 62, 63, 65, 67, 70, 71, 74, 76, 78, 79, 82, 83, 85, 87, 92, 93, 95, 97, 1022, 1023, 1025, 1027, 1032, 1033, 1035, 1037, 1052, 1053, 1055, 1057, 1072, 1073, 1075
OFFSET
1,1
MATHEMATICA
Select[Range[1200], Count[IntegerDigits[#], _?PrimeQ]== IntegerLength[#]/2&] (* Harvey P. Dale, Jun 02 2011 *)
CROSSREFS
Cf. A085520.
Sequence in context: A076979 A365589 A085520 * A175225 A187234 A127354
KEYWORD
base,easy,nonn
AUTHOR
Jason Earls, Jul 04 2003
STATUS
approved