This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A217051 #16 Apr 06 2020 19:03:05 %S A217051 3164252736,258479,69636,15165,3123,1019,1315,815,307,205,475,347,143, %T A217051 151,272,1388,618,245,12080,48,8635,23,287467,17,23118,8440,48387, %U A217051 127009,65457,70662,13181,42911,4965,162192,14460,226994,12,55853,4104749,2674855 %N A217051 Smallest k such that the number k^n in its decimal representation has a prime number of copies of the digit d for each d from 0 through 9. %e A217051 23^23 = 20880467999847912034355032910567 has a prime number of copies of each digit (two 1's and two 6's; three 2's, 3's, 4's, 5's, 7's and 8's; and five each of 9's and 0's), and no k < 23 is such that k^23 has this property. %Y A217051 Cf. A216855. %K A217051 nonn,base %O A217051 2,1 %A A217051 _James G. Merickel_, Sep 25 2012