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A359021
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Number of inequivalent tilings of a 5 X n rectangle using integer-sided square tiles.
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10
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1, 1, 5, 10, 39, 77, 521, 1985, 8038, 32097, 130125, 525676, 2131557, 8635656, 35017970, 141968455, 575692056, 2334344849, 9465939422, 38384559168, 155652202456, 631178976378, 2559476952229, 10378857744374, 42087027204278, 170665938023137, 692062856184512
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OFFSET
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0,3
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LINKS
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FORMULA
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For even n > 5:
For odd n > 5:
where
fixed_md(1)=1, fixed_md(2)=3, fixed_md(3)=15 and for n > 3, fixed_md(n) = A054857(n-1) + A054857(n-2) + fixed_md(n-2)+ fixed_md(n-1) + 2*A054857(n-3) + fixed_md(n-3).
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EXAMPLE
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a(2) is 5 because of:
+-+-+ +-+-+ +-+-+ +-+-+ +-+-+
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+-+-+ +-+-+ + + + + +-+-+
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+-+-+ + + +-+-+ +-+-+ + +
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+-+-+ +-+-+ +-+-+ +-+-+ +-+-+
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+-+-+ + + + + +-+-+ +-+-+
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+-+-+ +-+-+ +-+-+ +-+-+ +-+-+
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CROSSREFS
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Sequences for fixed and free (inequivalent) tilings of m X n rectangles, for 2 <= m <= 10:
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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