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A219974
Number of tilings of a 10 X n rectangle using straight (3 X 1) trominoes and 2 X 2 tiles.
1
1, 0, 7, 58, 286, 3068, 29876, 214485, 1910822, 17671945, 141365332, 1225043571, 10871708273, 90688536786, 781019641877, 6800784990468, 57716277595775, 496096480109463, 4284929501626939, 36621478929328140, 314572431365390797, 2707867101849205129
OFFSET
0,3
EXAMPLE
a(2) = 7, because there are 7 tilings of a 10 X 2 rectangle using straight (3 X 1) trominoes and 2 X 2 tiles:
.___. .___. .___. .___. .___. .___. .___.
| | | | | | | | | | | | | | | | |
|___| |___| |___| | | | |___| | | | | | |
| | | | | | | |_|_| | | | |_|_| |_|_|
|___| |___| | | | | | | | | | | | | |
| | | | | |_|_| |___| |_|_| |___| | | |
|___| | | | | | | | | | | | | | |_|_|
| | |_|_| |___| |___| | | | | | | | |
|___| | | | | | | | | | |_|_| |_|_| |___|
| | | | | | | | | | | | | | | | |
|___| |_|_| |_|_| |_|_| |___| |___| |___|
CROSSREFS
Column k=10 of A219967.
Sequence in context: A290847 A324420 A225160 * A266051 A202975 A051816
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Dec 02 2012
STATUS
approved