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A219952
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Number of tilings of an n X n square using right trominoes and 2 X 2 tiles.
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4
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1, 0, 1, 0, 6, 0, 545, 5504, 652036, 44013568, 11112714624, 3517475475328, 2781543486427548, 3568483481372543360, 9829161878198755474915, 48599777948701165162242560, 484370819140388708451108625276, 9036085159101926537420075859958528
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OFFSET
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0,5
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LINKS
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EXAMPLE
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a(4) = 6, because there are 6 tilings of a 4 X 4 square using right trominoes and 2 X 2 tiles:
.___.___. .___.___. .___.___. .___.___. .___.___. .___.___.
| . | . | | ._|_. | | ._| . | | ._|_. | | ._|_. | | . |_. |
|___|___| |_| . |_| |_| |___| |_| ._|_| |_|_. |_| |___| |_|
| . | . | | |___| | | |___| | | |_| . | | . |_| | | |___| |
|___|___| |___|___| |___|___| |___|___| |___|___| |___|___|
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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