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 A297349 #13 Feb 16 2025 08:33:52
%S A297349 1,41,1201,36281,1094401,33014921,995960401,30045123161,906370788001,
%T A297349 27342474236201,824840018262001,24882936703189241,750643185668251201,
%U A297349 22644641945255809481,683120580615598976401,20607688511425541428121,621671836326816125138401
%N A297349 Number of edge covers in the 2 X n king graph.
%H A297349 Andrew Howroyd, <a href="/A297349/b297349.txt">Table of n, a(n) for n = 1..200</a>
%H A297349 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/EdgeCover.html">Edge Cover</a>
%H A297349 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/KingGraph.html">King Graph</a>
%H A297349 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (29,36,-24).
%F A297349 a(n) = 29*a(n-1) + 36*a(n-2) - 24*a(n-3) for n > 3.
%F A297349 G.f.: x*(1 + 12*x - 24*x^2)/(1 - 29*x - 36*x^2 + 24*x^3).
%t A297349 (* Start from _Eric W. Weisstein_, Dec 29 2017 *)
%t A297349 Table[-RootSum[24 - 36 # - 29 #^2 + #^3 &, -9152 #^n - 1682 #^(n + 1) + 65 #^(n + 2) &]/16889, {n, 20}]
%t A297349 -RootSum[24 - 36 # - 29 #^2 + #^3 &, #^Range[20] (-9152 - 1682 # + 65 #^2) &]/16889
%t A297349 LinearRecurrence[{29, 36, -24}, {1, 41, 1201}, 20]
%t A297349 CoefficientList[Series[(1 + 12 x - 24 x^2)/(1 - 29 x - 36 x^2 + 24 x^3), {x, 0, 20}], x]
%t A297349 (* End *)
%o A297349 (PARI) Vec(x*(1 + 12*x - 24*x^2)/(1 - 29*x - 36*x^2 + 24*x^3) + O(x^20))
%Y A297349 Row 2 of A297205.
%K A297349 nonn
%O A297349 1,2
%A A297349 _Andrew Howroyd_, Dec 28 2017