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A032119 Number of labeled series-reduced dyslexic planted planar trees (root unlabeled) with n leaves. 1
1, 1, 6, 57, 750, 12645, 260190, 6322365, 177181830, 5625873225, 199608636150, 7826601269025, 336070622037150, 15684327120386925, 790493799998652750, 42790196611446409125, 2475921578709979149750, 152499324058939789556625, 9961887269457311273835750, 687922376268803482237055625 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..200

C. G. Bower, Transforms (2)

Cassandra Durell, Stefan Forcey, Level-1 Phylogenetic Networks and their Balanced Minimum Evolution Polytopes, arXiv:1905.09160 [math.CO], 2019.

Index entries for sequences related to rooted trees

FORMULA

Doubles (index 2+) under "BIJ" (reversible, indistinct, labeled) transform.

E.g.f.: series reversion of x*(2 - 3*x)/(2*(1-x)). - Andrew Howroyd, Sep 19 2018

MATHEMATICA

m = 21; egf = InverseSeries[x(2 - 3x)/(2(1-x)) + O[x]^m];

CoefficientList[egf, x]*Range[0, m-1]! // Rest (* Jean-Fran├žois Alcover, Sep 25 2019 *)

PROG

(PARI) Vec(serlaplace(serreverse(x*(2 - 3*x)/(2*(1-x)) + O(x^20)))) \\ Andrew Howroyd, Sep 19 2018

CROSSREFS

Sequence in context: A308863 A000406 A305276 * A294511 A242817 A295238

Adjacent sequences:  A032116 A032117 A032118 * A032120 A032121 A032122

KEYWORD

nonn,eigen

AUTHOR

Christian G. Bower

EXTENSIONS

Terms a(18) and beyond from Andrew Howroyd, Sep 19 2018

STATUS

approved

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Last modified November 20 05:07 EST 2019. Contains 329323 sequences. (Running on oeis4.)