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Prime numbers for which the number of odd nonprime digits equals the number of even nonzero digits and both are >0.
1

%I #9 Dec 22 2023 12:22:49

%S 29,41,61,89,127,163,167,239,251,271,293,349,389,401,409,431,439,479,

%T 521,541,569,601,613,617,631,659,761,769,809,839,859,947,967,983,1063,

%U 1087,1229,1237,1249,1277,1289,1327,1367,1429,1433,1453,1481,1489,1523,1543

%N Prime numbers for which the number of odd nonprime digits equals the number of even nonzero digits and both are >0.

%C Odd nonprime digits are 1 or 9 and even digits are 2, 4, 6 or 8.

%H Harvey P. Dale, <a href="/A157141/b157141.txt">Table of n, a(n) for n = 1..1000</a>

%t pdQ[p_]:=Count[IntegerDigits[p],_?(MemberQ[{1,9},#]&)]==Count[IntegerDigits[p],_?(MemberQ[ {2,4,6,8},#]&)]>0; Select[Prime[Range[250]],pdQ] (* _Harvey P. Dale_, Dec 22 2023 *)

%Y Cf. A000040.

%K nonn,base,less

%O 1,1

%A _Juri-Stepan Gerasimov_, Feb 24 2009

%E Definition corrected, 1277 and 1289 inserted by _R. J. Mathar_, May 15 2010