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 A112584 #3 Mar 31 2012 10:30:58 %S A112584 1,8,4,50,63,39,461,78,12203,312,318880,2184,57725,5804,6698,9722 %N A112584 Lengths of the loop of the sequences "Sum of last n digits" beginning with (n-1) zeros followed by digit 5. %e A112584 a(4)=50 because the sum of last four *digits* of the sequence beginning with 0,0,0,5, (three zeros followed by a 5) enters in a loop whose length is 50 terms; so a(4)=50 %e A112584 a(5)=63 because "Sum of last five digits" beginning with 0,0,0,0,5 enters in a cycle of 63 terms. %e A112584 Computed by Michael D Beeler. %Y A112584 Cf. A112395. %K A112584 base,easy,nonn %O A112584 1,2 %A A112584 _Alexandre Wajnberg_, Dec 17 2005