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Number of tilings of a 9 X n rectangle using dominoes and straight (3 X 1) trominoes.
2

%I #8 Dec 07 2012 12:41:45

%S 1,5,249,17395,862953,53074167,3105936858,181382499259,10750194262698,

%T 631206895803116,37197513508819191,2191568660367709311,

%U 129026759279686110418,7600920859497795763717,447657086066162084823497,26365510156948695071183306

%N Number of tilings of a 9 X n rectangle using dominoes and straight (3 X 1) trominoes.

%H Alois P. Heinz, <a href="/A219872/b219872.txt">Table of n, a(n) for n = 0..75</a>

%e a(1) = 5, because there are 5 tilings of a 9 X 1 rectangle using dominoes and straight (3 X 1) trominoes:

%e ._. ._. ._. ._. ._.

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%Y Column k=9 of A219866.

%K nonn

%O 0,2

%A _Alois P. Heinz_, Nov 30 2012