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A220297
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Number of ways to cut a 4 X n rectangle into rectangles with integer sides.
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4
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1, 8, 148, 3164, 70878, 1613060, 36911922, 846280548, 19415751782, 445550465628, 10225294476962, 234675373081668, 5385967300825942, 123612245431357148, 2837003283963428562, 65111601723938370628, 1494366038587416919782, 34296959750113321113308
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OFFSET
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0,2
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LINKS
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FORMULA
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G.f.: see Maple program.
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EXAMPLE
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a(1) = 8:
._. ._. ._. ._. ._. ._. ._. ._.
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MAPLE
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gf:= (3832*x^6 -8492*x^5 +6722*x^4 -2468*x^3 +441*x^2 -36*x+1) / (11680*x^6 -20980*x^5 +13840*x^4 -4280*x^3 +645*x^2 -44*x+1):
a:= n-> coeff(series(gf, x, n+1), x, n):
seq(a(n), n=0..20);
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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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