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%I #9 Dec 07 2012 12:45:27
%S 1,2,15,143,1069,9612,82634,707903,6155230,53074167,458901955,
%T 3968548571,34293794622,296497719200,2563023778341,22155553744380,
%U 191528023181443,1655649630655481,14312296720331975,123722938782920490,1069522524403416934,9245501816227527991
%N Number of tilings of a 5 X n rectangle using dominoes and straight (3 X 1) trominoes.
%H Alois P. Heinz, <a href="/A219868/b219868.txt">Table of n, a(n) for n = 0..500</a>
%e a(2) = 15, because there are 15 tilings of a 5 X 2 rectangle using dominoes and straight (3 X 1) trominoes:
%e .___. .___. .___. .___. .___. .___. .___. .___.
%e | | | |___| | | | |___| | | | |___| | | | |___|
%e | | | |___| |_|_| | | | | | | |___| |_|_| | | |
%e |_|_| |___| |___| |_|_| |_|_| |___| |___| |_|_|
%e | | | | | | | | | | | | |___| |___| |___| |___|
%e |_|_| |_|_| |_|_| |_|_| |___| |___| |___| |___|
%e .___. .___. .___. .___. ._._. ._._. .___.
%e | | | | | | |___| |___| | | | | | | |___|
%e |_|_| |_|_| |___| |___| |_| | | |_| | | |
%e | | | | | | | | | | | | | |_| |_| | | | |
%e | | | |_|_| | | | |_|_| | | | | | | |_|_|
%e |_|_| |___| |_|_| |___| |_|_| |_|_| |___|
%Y Column k=5 of A219866.
%K nonn
%O 0,2
%A _Alois P. Heinz_, Nov 30 2012
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