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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
OFFSET
1,3
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-François 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 A376100
KEYWORD
nonn,eigen
EXTENSIONS
Terms a(18) and beyond from Andrew Howroyd, Sep 19 2018
STATUS
approved