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 A020666 #16 Dec 05 2024 09:56:12 %S A020666 1023456789,32043,2326,763,309,159,56,104,49,36,25,15,25,17,17,15,16, %T A020666 7,5,6,6,5,11,9,14,5,5,5,5,9,5,8,11,4,4,6,5,7,3,5,4,4,6,4,3,6,3,3,4,4, %U A020666 5,4,3,6,4,4,3,4,4,3,3,3,3,3,3,4,3,2,3,2,3,3,3,3,4,3,3,3,2,3,4,2,3,2,3,3,2,2,2 %N A020666 a(n)^n is the least n-th power containing every digit. %C A020666 It is extremely probable that a(n) = 2 for all n >= 169. %H A020666 Seiichi Manyama, <a href="/A020666/b020666.txt">Table of n, a(n) for n = 1..10000</a> %o A020666 (Python) %o A020666 def a(n): %o A020666 if n == 1: return 1023456789 %o A020666 an = 2 %o A020666 while not(len(set(str(an**n))) == 10): an += 1 %o A020666 return an %o A020666 print([a(n) for n in range(1, 90)]) # _Michael S. Branicky_, Jul 04 2021 %Y A020666 Cf. A020667, A112388, A137214. %K A020666 nonn,base %O A020666 1,1 %A A020666 _David W. Wilson_