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 A031182 #13 Feb 16 2025 08:32:35 %S A031182 1,1,7,7,7,7,7,7,7,7,1,7,1,7,7,7,7,1,7,7,7,1,7,7,7,7,7,7,7,7,7,7,7,7, %T A031182 7,7,7,7,7,7,7,7,7,7,7,7,1,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,1,7,2,7, %U A031182 7,7,7,1,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7 %N A031182 Periods of sum of fourth powers of digits iterated until the sequence becomes periodic. %H A031182 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Digitaddition.html">Digitaddition</a> %K A031182 nonn,base %O A031182 0,3 %A A031182 _Eric W. Weisstein_ %E A031182 Missing a(0)=1 inserted by _Sean A. Irvine_, Apr 14 2020