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A098133
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Number of compositions of n where the smallest part is equal to the number of parts.
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0
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1, 0, 0, 1, 2, 2, 2, 2, 3, 5, 8, 11, 14, 17, 20, 24, 30, 39, 52, 69, 90, 115, 144, 177, 215, 260, 315, 384, 472, 584, 725, 900, 1114, 1372, 1679, 2041, 2466, 2965, 3553, 4250, 5082, 6081, 7285, 8738, 10490, 12597, 15121, 18130, 21699, 25912, 30865, 36670
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OFFSET
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1,5
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LINKS
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Table of n, a(n) for n=1..52.
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FORMULA
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G.f.: Sum((x^(m^2)-x^(m*(m+1)))/(1-x)^m, m=1..infinity).
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EXAMPLE
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a(9)=3 because we have [2,7],[7,2] and [3,3,3].
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MAPLE
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G:=sum((x^(m^2)-x^(m*(m+1)))/(1-x)^m, m=1..35):Gser:=series(G, x=0, 60): seq(coeff(Gser, x^n), n=1..58); (Deutsch)
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CROSSREFS
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Cf. A006141.
Sequence in context: A098527 A035635 A029100 * A138185 A225941 A138705
Adjacent sequences: A098130 A098131 A098132 * A098134 A098135 A098136
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KEYWORD
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easy,nonn,changed
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AUTHOR
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Vladeta Jovovic, Sep 27 2004
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EXTENSIONS
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More terms from Emeric Deutsch, Apr 18 2005
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STATUS
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approved
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