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 A022474 #8 Jun 27 2013 13:13:17
%S A022474 0,0,0,1,1,1,2,3,3,6,7,7,11,15,14,24,30,38,48,73,83,114,155,191,251,
%T A022474 336,426,560,737,964,1237,1628,2135,2726,3622,4680,6104,7948,10430,
%U A022474 13504,17662,23081,29965,39050,51143,66276,86674,112986,147161,191843,250259
%N A022474 Number of 3's in n-th term of A022470.
%H A022474 Peter J. C. Moses, <a href="/A022474/b022474.txt">Table of n, a(n) for n = 1..1000</a>
%t A022474 p={4,-7,7,-12,9,-4,6,-6,5,-5,10,-12,10,-11,8,-6,4,-2,5,-4,1,2,-9,16,-15,5,-6,0,3,12,-8,2,-6,-4,-3,12,-10,18,-8,3,-8,0,5,-6,7,-8,0,10,-9,4,-6,-2,11,0,2,-5,0,-3,1,-1,0,3,1,-2,-1,0,1,1,0,-1,0,0,0}; q={-6,9,-9,18,-16,11,-14,8,-1,5,-7,-2,-8,14,5,5,-19,-3,6,7,6,-16,7,-8,22,-17,12,-7,-5,-7,8,-4,7,9,-13,4,6,-14,14,-19,7,13,-2,4,-18,0,1,4,12,-8,5,0,-8,-1,-7,8,5,2,-3,-3,0,0,0,0,2,1,0,-3,-1,1,1,1,-1}; gf=Fold[x #1+#2&,0,p]/Fold[x #1+#2&,0,q]; CoefficientList[Series[gf,{x,0,99}],x] (* _Peter J. C. Moses_, Jun 23 2013 *)
%K A022474 nonn
%O A022474 1,7
%A A022474 _Clark Kimberling_