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 A248077 #14 Oct 14 2014 15:34:27 %S A248077 1,3,4,5,7,14,9,11,13,19 %N A248077 Least number k > 0 such that k^k contains exactly n distinct digits. %C A248077 Unlike A054039 and A247794, "...at least n..." and "...exactly n..." are two different sequences. a(n) above gives "...exactly n..." whereas, for "...at least n...", the sequence would be 1, 3, 4, 5, 7, 9, 9, 11, 13, 19, where a(6) would be 9 instead of 14. %e A248077 7^7 = 823543 has 5 distinct digits. 6^6, 5^5, 4^4, 3^3, 2^2, and 1^1 all do not have 5 distinct digits. So a(5) = 7. %o A248077 (PARI) %o A248077 a(n)=k=1; while(#vecsort(digits(k^k), , 8)!=n, k++); k %o A248077 vector(10,n,a(n)) %Y A248077 Cf. A000312, A054039, A247794, A239306. %K A248077 nonn,base,fini,full,easy %O A248077 1,2 %A A248077 _Derek Orr_, Sep 30 2014