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A157145

Prime numbers containing an equal, nonzero number of odd nonprime digits and of even prime digits.

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

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OFFSET

1,1

COMMENTS

Even prime digit = 2. Odd nonprime digits are 1 or 9.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

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

Adjacent sequences: A157142 A157143 A157144 * A157146 A157147 A157148

KEYWORD

nonn,base,less

AUTHOR

Juri-Stepan Gerasimov, Feb 24 2009

EXTENSIONS

Definition corrected and terms 2069..2089 inserted by R. J. Mathar, May 15 2010

STATUS

approved