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 A203070 #11 Mar 30 2012 18:51:46
%S A203070 1,2,3,4,10,6,28,8,9,10,121,12,13,28,30,16,68,18,608,20,84,242,23,24,
%T A203070 100,26,27,28,203,30,1550,160,363,68,280,36,1850,608,39,40,82,84,4988,
%U A203070 484,90,644,1222,48,784,100,204,52,212,54,1210,56,1824,1276,1003
%N A203070 Smallest positive multiple of n that is palindromic in base 3, ignoring trailing zeros.
%H A203070 Harvey P. Dale, <a href="/A203070/b203070.txt">Table of n, a(n) for n = 1..1000</a>
%t A203070 notpal3Q[i_]:=Module[{id=IntegerDigits[i,3]},While[Last[id]==0,id = Most[id]];id!=Reverse[id]]; lm3[n_]:=Module[{k=1},While[notpal3Q[k n],k++];k n]; Array[lm3,80]
%Y A203070 Cf. A141709.
%K A203070 nonn,base
%O A203070 1,2
%A A203070 _Harvey P. Dale_, Dec 28 2011