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%I #7 Dec 07 2012 12:51:34
%S 1,1,5,35,165,1177,9407,55657,372429,2766100,17671945,118674685,
%T 837152398,5531816082,37328192350,257252634864,1725117502706,
%U 11666552132346,79612474584518,537157628862720,3636277021289585,24711657036469040,167150255133278869
%N Number of tilings of a 9 X n rectangle using straight (3 X 1) trominoes and 2 X 2 tiles.
%H Alois P. Heinz, <a href="/A219973/b219973.txt">Table of n, a(n) for n = 0..50</a>
%e a(2) = 5, because there are 5 tilings of a 9 X 2 rectangle using straight (3 X 1) trominoes and 2 X 2 tiles:
%e .___. .___. .___. .___. .___.
%e | | | | | | | | | | | |
%e | | | | | | |___| |___| |___|
%e |_|_| |_|_| | | | | | | |
%e | | | | | | | | |___| |___|
%e | | | |___| |_|_| | | | | |
%e |_|_| | | | | | | | |___|
%e | | | |___| |___| |_|_| | | |
%e | | | | | | | | | | | |
%e |_|_| |___| |___| |___| |_|_|
%Y Column k=9 of A219967.
%K nonn
%O 0,3
%A _Alois P. Heinz_, Dec 02 2012