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 A027166 #13 Oct 24 2019 18:20:08
%S A027166 1,4,14,36,103,248,684,1624,4445,10524,28762,68060,185955,439984,
%T A027166 1202072,2844144,7770361,18384884,50228454,118841812,324681887,
%U A027166 768205608,2098776772,4965759176,13566706389,32099171980,87696568754,207492309516,566879531803
%N A027166 a(n) = Sum_{0<=j<=i<=n} A027157(i, j).
%H A027166 Colin Barker, <a href="/A027166/b027166.txt">Table of n, a(n) for n = 0..1000</a>
%H A027166 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (2,5,-12,9,-6,3).
%F A027166 From _Colin Barker_, Feb 20 2016: (Start)
%F A027166 a(n) = 2*a(n-1)+5*a(n-2)-12*a(n-3)+9*a(n-4)-6*a(n-5)+3*a(n-6) for n>5.
%F A027166 G.f.: (1+x)^2 / ((1-x)^2*(1-6*x^2-3*x^4)).
%F A027166 (End)
%t A027166 LinearRecurrence[{2,5,-12,9,-6,3},{1,4,14,36,103,248},30] (* _Harvey P. Dale_, Apr 18 2019 *)
%o A027166 (PARI) Vec((1+x)^2/((1-x)^2*(1-6*x^2-3*x^4)) + O(x^40)) \\ _Colin Barker_, Feb 20 2016
%Y A027166 Partial sums of A027164.
%K A027166 nonn,easy
%O A027166 0,2
%A A027166 _Clark Kimberling_