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%I #31 Apr 17 2015 18:11:42
%S 59,67,88,104,107,108,113,114,118,120,141,146,150,156,190,214,444,
%T 880628
%N Numbers n such that 2^n in decimal has at least 8 of the digits 0-9 appearing a prime number times.
%C Heuristically, all digits appear a prime number of times for an infinite number of values of n. A216873 contains the subset with 9 in place of 8.
%C a(19) > 5000000. - _James G. Merickel_, Apr 17 2015
%o (PARI)
%o /* program prints asterisks for values giving 9 instead of just 8,
%o and stops if all digits appear a prime number of times. */
%o { a=2;p=1;while(p,b=a;c=vectorsmall(10);while(b,
%o d=b%10;b\=10;c[d+1]++;next());e=3;for(i=1,10,
%o if(isprime(c[i])==0,e--;if(e==0,break())));if(e,
%o print1(p);if(e>1,print1("*");if(e==3,break()));print1("\n"));
%o p++;a+=a;next()) }
%Y Cf. A216873.
%K nonn,base,hard
%O 1,1
%A _James G. Merickel_, Sep 18 2012
%E a(18) added by _James G. Merickel_, Jul 07 2013
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