%I #11 Aug 29 2015 02:14:49
%S 1,21,1563,162409,17508475,1894621633,205109410835,22206188455913,
%T 2404176415007051,260291084969169553,28180738494571199683,
%U 3051022897700513626745,330322812747235906893563,35762812820215620676404385,3871905699058282397207463923
%N Number of domicule tilings of a 5 X 2n grid.
%C A domicule is either a domino or it is formed by the union of two neighboring unit squares connected via their corners. In a tiling the connections of two domicules are allowed to cross each other.
%H Alois P. Heinz, <a href="/A239267/b239267.txt">Table of n, a(n) for n = 0..450</a>
%F G.f.: -(2048*x^7 -7680*x^6 -25472*x^5 +42048*x^4 -18928*x^3 +2912*x^2 -124*x+1) / (16384*x^8 -58112*x^7 -180608*x^6 +352480*x^5 -201552*x^4 +46976*x^3 -4394*x^2 +145*x-1).
%p gf:= -(2048*x^7 -7680*x^6 -25472*x^5 +42048*x^4 -18928*x^3 +2912*x^2 -124*x+1) / (16384*x^8 -58112*x^7 -180608*x^6 +352480*x^5 -201552*x^4 +46976*x^3 -4394*x^2 +145*x-1):
%p a:= n-> coeff(series(gf, x, n+1), x, n):
%p seq(a(n), n=0..20);
%Y Even bisection of column k=5 of A239264.
%K nonn,easy
%O 0,2
%A _Alois P. Heinz_, Mar 13 2014
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