cp's OEIS Frontend

A219869 Number of tilings of a 6 X n rectangle using dominoes and straight (3 X 1) trominoes.

%I A219869 #8 Dec 07 2012 12:45:04
%S A219869 1,2,30,472,5624,82634,1143834,15859323,223026907,3105936858,
%T A219869 43427618185,606962113407,8477372675760,118475405895601,
%U A219869 1655302050975409,23128348583334118,323168394713538001,4515400902297318144,63091618970759626487,881547198837947075202
%N A219869 Number of tilings of a 6 X n rectangle using dominoes and straight (3 X 1) trominoes.
%H A219869 Alois P. Heinz, <a href="/A219869/b219869.txt">Table of n, a(n) for n = 0..300</a>
%e A219869 a(1) = 2, because there are 2 tilings of a 6 X 1 rectangle using dominoes and straight (3 X 1) trominoes:
%e A219869 ._.    ._.
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%Y A219869 Column k=6 of A219866.
%K A219869 nonn
%O A219869 0,2
%A A219869 _Alois P. Heinz_, Nov 30 2012