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A237356
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The number of tilings of the 3 X 4 X (2n) room with 1 X 2 X 2 boxes.
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2
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1, 29, 1065, 41097, 1602289, 62603505, 2447085377, 95662064129, 3739717169185, 146197357313057, 5715321341103969, 223430193355808865, 8734601289109031137, 341463519887132765409, 13348901883923975256545, 521851299448684501083617, 20400837546324144424724449, 797534035150318477886048225, 31178158042817899845549718497
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OFFSET
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0,2
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COMMENTS
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The count compiles all arrangements without respect to symmetry: Stacks that are equivalent after rotations or flips through any of the 3 axes or 3 planes are counted with multiplicity.
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LINKS
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FORMULA
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G.f.: (1-2*x)*(-120*x^3+122*x^2-24*x+1) / ( (1-x) *(2640*x^4-2540*x^3+646*x^2-54*x+1) ) .
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MAPLE
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(1-2*x)*(-120*x^3+122*x^2-24*x+1) / ( (1-x) *(2640*x^4-2540*x^3+646*x^2-54*x+1) ) ;
coeftayl(%, x=0, n) ;
end proc:
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MATHEMATICA
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CoefficientList[Series[(1 - 2 x) (-120 x^3 + 122 x^2 - 24 x + 1)/((1 - x) (2640 x^4 - 2540 x^3 + 646 x^2 - 54 x + 1)), {x, 0, 30}], x] (* Vincenzo Librandi, Feb 08 2014 *)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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