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A010758
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Sum along upward diagonal of Pascal triangle from (but not including) halfway point.
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3
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0, 0, 1, 2, 1, 3, 7, 14, 11, 25, 51, 97, 92, 189, 365, 674, 709, 1383, 2587, 4685, 5270, 9955, 18228, 32551, 38403, 70954, 127921, 226007, 276408, 502415, 895103, 1568062, 1972851, 3540913, 6249235, 10871723, 13996408, 24868131, 43551364, 75326395, 98847749
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OFFSET
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0,4
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LINKS
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FORMULA
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a(n) = Sum_{k = 1 + floor(n/4)..floor(n/2)} binomial(n - k, k). - Sean A. Irvine, Jun 09 2018
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PROG
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(PARI) a(n) = sum(k=n\4+1, n\2, binomial(n-k, k)); \\ Seiichi Manyama, Feb 10 2022
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CROSSREFS
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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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