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 A114196 #8 Jul 31 2015 18:12:30
%S A114196 1,3,10,35,127,472,1781,6783,25978,99823,384331,1481424,5714073,
%T A114196 22048715,85098282,328485899,1268080423,4895497064,18899853101,
%U A114196 72967061671,281708048154,1087611942455,4199040207827,16211637659168
%N A114196 Expansion of (1-3x)/(1-6x+8x^2+x^3).
%C A114196 Diagonal sums of A114195.
%H A114196 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (6, -8, -1).
%F A114196 a(n)=6a(n-1)-8a(n-2)-a(n-3); a(n)=sum{k=0..floor(n/2), sum{j=0..n-k, C(n-k, j)C(j+k, 2k)2^(j-k)}}.
%t A114196 CoefficientList[Series[(1-3x)/(1-6x+8x^2+x^3),{x,0,30}],x] (* or *) LinearRecurrence[{6,-8,-1},{1,3,10},30] (* _Harvey P. Dale_, Feb 02 2012 *)
%K A114196 easy,nonn
%O A114196 0,2
%A A114196 _Paul Barry_, Nov 16 2005