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 A031200 #13 Feb 16 2025 08:32:36 %S A031200 1,1,92,14,30,92,56,6,92,56,1,92,27,30,92,56,30,12,27,21,92,27,2,92, %T A031200 27,30,12,56,30,92,14,30,92,56,21,92,56,30,92,27,30,92,27,21,92,27,30, %U A031200 12,56,30,92,56,30,92,27,30,92,56,30,12,56,30,12,56,30,92,56,30 %N A031200 Periods of sum of 7th powers of digits iterated until the sequence becomes periodic. %H A031200 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Digitaddition.html">Digitaddition</a> %K A031200 nonn,base %O A031200 0,3 %A A031200 _Eric W. Weisstein_ %E A031200 Missing a(0)=1 inserted by _Sean A. Irvine_, Apr 14 2020