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A109222
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Row sums of a triangle related to the Fibonacci polynomials.
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4
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1, 2, 3, 6, 11, 21, 40, 76, 145, 276, 526, 1002, 1909, 3637, 6929, 13201, 25150, 47915, 91286, 173915, 331337, 631252, 1202640, 2291229, 4365172, 8316378, 15844082, 30185609, 57508601, 109563441, 208736561, 397677834, 757642355, 1443434582
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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G.f.: (1 + x - x^2 - x^3)/(1 - x - 2x^2 + x^4);
a(n) = a(n-1) + 2a(n-2) - a(n-4);
a(n) = Sum_{k=0..n} binomial(floor((2n-k)/2)+n-k, 2n-2k).
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MAPLE
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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