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%I #8 Jan 28 2023 22:07:32
%S 3,105,3665,123215,4051679,131630449,4248037953,136587740399,
%T 4382607093471,140457446235441,4498520188148993,144023056568886959,
%U 4610014925578108703,147543642097619999089,4721816707356538941633,151105755554498621737583,4835522406931884652356447
%N Number of edge cuts in the 3 X n grid graph.
%H Andrew Howroyd, <a href="/A359988/b359988.txt">Table of n, a(n) for n = 1..200</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (54,-777,2390,-1736,256).
%F a(n) = 54*a(n-1) - 777*a(n-2) + 2390*a(n-3) - 1736*a(n-4) + 256*a(n-5) for n > 5.
%F G.f.: x*(3 - 57*x + 326*x^2 - 280*x^3 + 32*x^4)/((1 - 32*x)*(1 - 22*x + 73*x^2 - 54*x^3 + 8*x^4)).
%F a(n) = A013823(n-1) - A158453(n).
%o (PARI) Vec((3 - 57*x + 326*x^2 - 280*x^3 + 32*x^4)/((1 - 32*x)*(1 - 22*x + 73*x^2 - 54*x^3 + 8*x^4)) + O(x^20))
%Y Row 3 of A359990.
%Y Cf. A013823, A158453, A359987.
%K nonn,easy
%O 1,1
%A _Andrew Howroyd_, Jan 28 2023
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