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A098133 Number of compositions of n in which the smallest part is equal to the number of parts. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..52.

FORMULA

G.f.: Sum_{m>=1} (x^(m^2) - x^(m*(m+1)))/(1-x)^m.

EXAMPLE

a(9)=3 because we have [2,7], [7,2] and [3,3,3].

MAPLE

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); # Emeric Deutsch, Apr 18 2005

CROSSREFS

Cf. A006141.

Sequence in context: A114869 A316899 A029100 * A138185 A225941 A138705

Adjacent sequences:  A098130 A098131 A098132 * A098134 A098135 A098136

KEYWORD

easy,nonn,changed

AUTHOR

Vladeta Jovovic, Sep 27 2004

EXTENSIONS

More terms from Emeric Deutsch, Apr 18 2005

STATUS

approved

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Last modified August 20 14:06 EDT 2019. Contains 326152 sequences. (Running on oeis4.)