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A144791
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Euler transform of A141199.
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1
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1, 4, 11, 34, 93, 269, 735, 2037, 5515, 14912, 39828, 105931, 279408, 733409, 1913349, 4968092, 12835746, 33020764, 84586922, 215844162, 548725545, 1390140594, 3510064528, 8834980324, 22171254453, 55479601543, 138448505906, 344594242788, 855538158016
(list;
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listen;
history;
text;
internal format)
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OFFSET
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1,2
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REFERENCES
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Thomas Wieder: The number of certain rankings and hierarchies formed from labeled or unlabeled elements and sets, Applied Mathematical Sciences, vol. 3, 2009, no. 55, 2707 - 2724. [From Thomas Wieder, Nov 14 2009]
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LINKS
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Alois P. Heinz, Table of n, a(n) for n = 1..100
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FORMULA
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G.f.: 1 / prod_{k=1}^{inf} (1 - x^k)^A141199(k).
Let sum_{k|n} denote a sum over all divisors k of n. Then
a(n) = (1/n) sum_{k=1}^{n-1} c(k) A141199(n-k),
with c(n)= sum_{k|n} k A141199(k).
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CROSSREFS
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A141199, A144792, A144791.
Sequence in context: A127154 A062460 A098324 * A180305 A060925 A027045
Adjacent sequences: A144788 A144789 A144790 * A144792 A144793 A144794
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KEYWORD
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nonn
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AUTHOR
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Thomas Wieder, Sep 21 2008
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EXTENSIONS
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More terms from Alois P. Heinz, Apr 21 2012
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STATUS
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approved
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