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%I #15 Jan 14 2023 12:41:34
%S 1,1,11,29,165,593,2773,11093,48605,201829,864901,3638261,15472261,
%T 65377669,277294885,1173523013,4972873413,21056700293,89200845765,
%U 377774394309,1600161267781,6777276186821,28705824305861,121582507360709
%N Number of tilings of a 4 X n rectangle using dominoes and 2 X 2 tiles.
%C The sequence is based on A352431.
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (3,10,-18,-14,20).
%F G.f.:(1 - 2*x - 2*x^2 + 4*x^3)/(1 - 3*x - 10*x^2 + 18*x^3 + 14*x^4 - 20*x^5).
%F a(n) = 3*a(n-1) + 10*a(n-2) - 18*a(n-3) - 14*a(n-4) + 20*a(n-5).
%e a(2)=11:
%e ___ ___ ___ ___ ___ ___
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%e |___| |___| |___| |_|_| |___| |___|
%e | | | | | |___| | | | | |___|
%e |___| |_|_| |___| |___| |___| |___|
%e .
%e ___ ___ ___ ___ ___
%e |___| | | | |___| |___| | | |
%e | | |_|_| | | | |___| |_|_|
%e |___| | | | |_|_| | | | |___|
%e |___| |_|_| |___| |_|_| |___|
%Y Cf. A352431, A352433.
%K nonn
%O 0,3
%A _Gerhard Kirchner_, Mar 17 2022
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