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A132790
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Row sums of triangle A132789.
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2
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1, 2, 6, 18, 53, 158, 486, 1550, 5109, 17298, 59799, 210048, 746983, 2682618, 9711214, 35390422, 129710309, 477769754, 1767525315, 6564644688, 24467315575, 91484660770, 343063807931, 1289912535908, 4861963178643, 18367386626558, 69533618024841, 263748085968060
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) = Sum_{k=1..n} binomial(n-1,k-1)*(1 + binomial(n,k-1)/k) - 1. - Andrew Howroyd, Sep 01 2018
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EXAMPLE
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a(4) = 18 = sum of row 4 terms of triangle A132789: (1 + 8 + 8 + 1).
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PROG
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(PARI) a(n)=sum(k=1, n, binomial(n-1, k-1)*(1 + binomial(n, k-1)/k) - 1); \\ Andrew Howroyd, Sep 01 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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