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A097941
Total number of smallest parts in all compositions of n.
5
1, 3, 6, 15, 31, 72, 155, 340, 738, 1595, 3424, 7335, 15642, 33243, 70432, 148808, 313571, 659188, 1382682, 2894369, 6047397, 12613209, 26265098, 54610722, 113387831, 235117449, 486933645, 1007290340, 2081469759, 4296789924
OFFSET
1,2
LINKS
Knopfmacher, Arnold; Munagi, Augustine O. Smallest parts in compositions, Kotsireas, Ilias S. (ed.) et al., Advances in combinatorics. In part based on the 3rd Waterloo workshop on computer algebra (WWCA, W80) 2011, Waterloo, Canada, May 26-29, 2011. Berlin: Springer. 197-207 (2013).
FORMULA
G.f.: (1-x)^2*Sum(x^k/(1-x-x^k)^2, k=1..infinity).
a(n) ~ n*2^(n-3). - Vaclav Kotesovec, Apr 30 2014
MATHEMATICA
Drop[ CoefficientList[ Series[(1 - x)^2*Sum[x^k/(1 - x - x^k)^2, {k, 50}], {x, 0, 30}], x], 1] (* Robert G. Wilson v, Sep 08 2004 *)
CROSSREFS
Cf. A092269.
Sequence in context: A034739 A276670 A244706 * A317792 A293732 A117161
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Sep 05 2004
EXTENSIONS
More terms from Robert G. Wilson v, Sep 08 2004
STATUS
approved