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 A374709 #10 Jul 20 2024 11:29:54
%S A374709 0,1,20,132,512,1485,3564,7504,14336,25425,42500,67716,103680,153517,
%T A374709 220892,310080,425984,574209,761076,993700,1280000,1628781,2049740,
%U A374709 2553552,3151872,3857425,4684004,5646564,6761216,8045325,9517500,11197696,13107200,15268737,17706452
%N A374709 a(n) = n*(6*n^4 + 8*n^3 + 1 - (-1)^n)/16.
%H A374709 <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (4, -4, -4, 10, -4, -4, 4, -1).
%F A374709 O.g.f.: x*(1 + 16*x + 56*x^2 + 68*x^3 + 35*x^4 + 4*x^5)/((1 - x)^6*(1 + x)^2).
%F A374709 a(n) = 4*a(n-1) - 4*a(n-2) - 4*a(n-3) + 10*a(n-4) - 4*a(n-5) - 4*a(n-6) + 4*a(n-7) - a(n-8) for n > 7.
%F A374709 E.g.f.: x*((8 + 73*x + 99*x^2 + 34*x^3 + 3*x^4)*cosh(x) + (7 + 73*x + 99*x^2 + 34*x^3 + 3*x^4)*sinh(x))/8.
%F A374709 a(2*n) = 4*A229147(n) = 4*A000583(n)*A016789(n).
%t A374709 LinearRecurrence[{4,-4,-4,10,-4,-4,4,-1},{0,1,20,132,512,1485,3564,7504},35]
%Y A374709 Row sums of A374708.
%Y A374709 Cf. A000583, A016789, A229147.
%K A374709 nonn,easy
%O A374709 0,3
%A A374709 _Stefano Spezia_, Jul 17 2024