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A132790 Row sums of triangle A132789. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..200

FORMULA

a(n) = Sum_{k=1..n} binomial(n-1,k-1)*(1 + binomial(n,k-1)/k) - 1. - Andrew Howroyd, Sep 01 2018

EXAMPLE

a(4) = 18 = sum of row 4 terms of triangle A132789: (1 + 8 + 8 + 1).

PROG

(PARI) a(n)=sum(k=1, n, binomial(n-1, k-1)*(1 + binomial(n, k-1)/k) - 1); \\ Andrew Howroyd, Sep 01 2018

CROSSREFS

Cf. A132789.

Sequence in context: A252822 A094864 A120010 * A214799 A072850 A254941

Adjacent sequences:  A132787 A132788 A132789 * A132791 A132792 A132793

KEYWORD

nonn

AUTHOR

Gary W. Adamson, Aug 30 2007

EXTENSIONS

Terms a(11) and beyond from Andrew Howroyd, Sep 01 2018

STATUS

approved

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Last modified April 3 04:21 EDT 2020. Contains 333195 sequences. (Running on oeis4.)