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 A073731 #3 Mar 30 2012 18:50:25
%S A073731 10,1,12,13,14,15,16,17,18,19,20,21,2,23,24,25,26,27,28,29,30,31,32,3,
%T A073731 34,35,36,37,38,39,40,41,42,43,4,45,46,47,48,49,50,51,52,53,54,5,56,
%U A073731 57,58,59,60,61,62,63,64,65,6,67,68,69,70,71,72,73,74,75,76,7,78,79,80,81,82,83,84,85,86,87,8,89,90,91,92,93,94,95,96,97,98,9
%N A073731 Least k such that A073729(k) = n.
%C A073731 The sequence is finite as 10 <= A073729(n) <= 99 for all n; a(n) = (if n mod 11 > 0 then n else n mod 10) for 10<=n<=99: the range is {n | 1<=n<=99}.
%F A073731 a(n) = n mod 10 + signum(n mod 11) * (n - n mod 10) for 10<=n<=99.
%K A073731 nonn,base,fini,full
%O A073731 10,1
%A A073731 _Reinhard Zumkeller_, Aug 05 2002