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A157020
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Sum_{d|n} d*binomial(n/d+d-2,d-1).
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1
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1, 3, 4, 9, 6, 22, 8, 33, 28, 46, 12, 131, 14, 78, 136, 177, 18, 307, 20, 456, 302, 166, 24, 1149, 376, 222, 568, 1177, 30, 2387, 32, 1761, 958, 358, 2556, 5224, 38, 438, 1496, 7851, 42, 8317, 44, 4863, 9136, 622, 48, 20169, 6518, 11451, 3112, 8516, 54, 23734
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Equals row sums of triangle A157497 [From Gary W. Adamson & Mats Granvik (qntmpkt(AT)yahoo.com), Mar 01 2009]
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FORMULA
| G.f.: Sum_{n>=1} n*x^n/(1-x^n)^n.
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MAPLE
| add( d*binomial(n/d+d-2, d-1), d=numtheory[divisors](n) ) ;
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CROSSREFS
| Cf. A081543, A132065.
Cf. A157497 [From Gary W. Adamson & Mats Granvik (qntmpkt(AT)yahoo.com), Mar 01 2009]
Sequence in context: A168341 A083111 A132065 * A180253 A055225 A054791
Adjacent sequences: A157017 A157018 A157019 * A157021 A157022 A157023
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KEYWORD
| easy,nonn
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AUTHOR
| R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 21 2009
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