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 A378933 #11 Mar 02 2025 21:31:03
%S A378933 2,15,53,146,356,809,1759,3716,7702,15763,31993,64582,129912,260749,
%T A378933 522627,1046616,2094858,4191639,8385533,16773690,33550412,67104305,
%U A378933 134212583,268429676,536864446,1073734619,2147475649,4294958446,8589924832,17179858453
%N A378933 Number of minimal edge cuts in the 3 X n grid graph.
%H A378933 Andrew Howroyd, <a href="/A378933/b378933.txt">Table of n, a(n) for n = 1..200</a>
%H A378933 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (6,-14,16,-9,2).
%F A378933 a(n) = 16*2^n - (2*n^3 + 9*n^2 + 73*n + 96)/6.
%F A378933 G.f.: x*(2 + 3*x - 9*x^2 + 6*x^3)/((1 - 2*x)*(1 - x)^4).
%F A378933 a(n) = A166761(n)/2.
%t A378933 LinearRecurrence[{6, -14, 16, -9, 2}, {2, 15, 53, 146, 356}, 30] (* _Paolo Xausa_, Mar 02 2025 *)
%o A378933 (PARI) a(n) = {16*2^n - (2*n^3 + 9*n^2 + 73*n + 96)/6}
%Y A378933 Row 3 of A378932.
%Y A378933 Cf. A166761, A359988, A378934.
%K A378933 nonn,easy
%O A378933 1,1
%A A378933 _Andrew Howroyd_, Dec 11 2024