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A157145
Prime numbers containing an equal, nonzero number of odd nonprime digits and of even prime digits.
1
29, 127, 239, 241, 251, 269, 271, 281, 293, 421, 521, 821, 829, 1229, 1237, 1277, 1283, 1327, 1423, 1427, 1523, 1627, 1723, 1823, 2017, 2039, 2069, 2081, 2089, 2129, 2137, 2143, 2153, 2309, 2339, 2341, 2351, 2371, 2381, 2389, 2393, 2417, 2441, 2459, 2531
OFFSET
1,1
COMMENTS
Even prime digit = 2. Odd nonprime digits are 1 or 9.
LINKS
MATHEMATICA
onpdQ[n_]:=Module[{od=DigitCount[n, 10, 1]+DigitCount[n, 10, 9], ev= DigitCount[ n, 10, 2]}, od==ev>0]; Select[Prime[Range[400]], onpdQ] (* Harvey P. Dale, Aug 11 2019 *)
CROSSREFS
Cf. A000040.
Sequence in context: A287406 A233114 A264672 * A142438 A342823 A118097
KEYWORD
nonn,base,less
AUTHOR
EXTENSIONS
Definition corrected and terms 2069..2089 inserted by R. J. Mathar, May 15 2010
STATUS
approved