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 A165015 #6 Dec 25 2016 01:05:23 %S A165015 1,2,2,2,3,2,3,4,4,3,2,3,4,4,3,2,3,3,2,3,3,2,3,2,2,3,3,2,3,2,1,2,2,2, %T A165015 2,3,2,3,3,2,2,3,2,3,3,2,3,3,3,3,3,3,3,2,2,2,3,2,3,3,3,2,3,2,3,3,3,2, %U A165015 3,3,3,4,3,3,3,2,2,4,2,4,3,3,3,4,3,2,3,3,3,3,3,3,4,3,3,4,3,3,3,2,3,3,3,3,3 %N A165015 (Length of preperiodic part) + (length of cycle) of trajectory of n under iteration of the base-4 Kaprekar map in A165012. %H A165015 Joseph Myers, <a href="/A165015/b165015.txt">Table of n, a(n) for n = 0..1024</a> %H A165015 <a href="/index/K#Kaprekar_map">Index entries for the Kaprekar map</a> %Y A165015 Cf. A165012, A165014. %Y A165015 In other bases: A164886 (base 2), A164996 (base 3), A165035 (base 5), A165054 (base 6), A165074 (base 7), A165093 (base 8), A165113 (base 9), A151963 (base 10). %K A165015 base,nonn %O A165015 0,2 %A A165015 _Joseph Myers_, Sep 04 2009