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%I #10 Jan 19 2019 22:45:12
%S 11,19,41,61,89,101,103,107,109,113,131,139,149,151,163,167,179,181,
%T 191,193,197,199,211,241,269,281,311,349,389,401,409,419,421,431,439,
%U 443,449,461,463,467,479,487,491,499,509,541,569,599,601,607,613,617,619
%N Primes such that number of prime digits < number of nonprime digits.
%C Intersection of A085558 and A000040. - Charles R Greathouse IV_, Mar 25 2010
%e 101 is prime, its nonprime digits are (1, 0, 1), and 0<3 so a(6)=101. 103 is prime, its prime digit is 3, its nonprime digits are (0, 1), and 1 < 2 so a(7)=103.
%p a := proc (n) local nn, s, j: nn := convert(n, base, 10): s := 0: for j to nops(nn) do if isprime(nn[j]) = false then s := s+1 else s := s-1 end if end do: if isprime(n) = true and 0 < s then n else end if end proc: seq(a(n), n = 1 .. 650); # _Emeric Deutsch_, Jan 28 2009
%K nonn,base,easy,less
%O 1,1
%A _Juri-Stepan Gerasimov_, Jan 08 2009
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