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Odd numbers n with equal number of odd digits in n and n-th prime.
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%I #9 Sep 25 2020 18:47:41

%S 3,9,11,17,23,31,35,39,49,51,55,59,61,73,77,87,89,95,97,99,101,103,

%T 107,123,125,127,129,131,133,137,139,141,147,149,157,159,161,163,169,

%U 171,173,175,177,181,195,199,235,237,253,257,279,305,309,319,323,341,343

%N Odd numbers n with equal number of odd digits in n and n-th prime.

%C Odd digits are 1, 3, 5, 7 or 9.

%t Select[Range[1,401,2],Count[IntegerDigits[#],_?OddQ]==Count[ IntegerDigits[ Prime[#]],_?OddQ]&] (* _Harvey P. Dale_, Sep 25 2020 *)

%Y Cf. A000027, A000040, A155548.

%K nonn,base,less

%O 1,1

%A _Juri-Stepan Gerasimov_, Feb 24 2009

%E Corrected (105 replaced by 103, 305 inserted) by _R. J. Mathar_, May 15 2010