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Number of labeled dyslexic planted planar trees with n+1 nodes.
2

%I #18 Sep 08 2019 12:27:26

%S 1,2,9,72,840,12780,238770,5281920,134946000,3909578400,126638542800,

%T 4535037460800,177904622095200,7586967310322400,349479111223242000,

%U 17292052928037888000,914673660594613920000,51506610632458293312000,3076341001739003430432000

%N Number of labeled dyslexic planted planar trees with n+1 nodes.

%H Andrew Howroyd, <a href="/A038035/b038035.txt">Table of n, a(n) for n = 1..200</a>

%H C. G. Bower, <a href="/transforms2.html">Transforms (2)</a>

%H <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a>

%F Divides by n and shifts left under "BIJ" (reversible, indistinct, labeled) transform.

%F E.g.f.: series reversion of 2*x*(1 - x)/(2 - x^2). - _Andrew Howroyd_, Sep 19 2018

%t m = 20;

%t CoefficientList[InverseSeries[2*x*(1 - x)/(2 - x^2) + O[x]^m], x]*Range[0, m - 1]! // Rest (* _Jean-François Alcover_, Sep 08 2019 *)

%o (PARI) Vec(serlaplace(serreverse(2*x*(1 - x)/(2 - x^2) + O(x^20)))) \\ _Andrew Howroyd_, Sep 19 2018

%Y Cf. A005470, A032128.

%K nonn,eigen

%O 1,2

%A _Christian G. Bower_, Sep 15 1998

%E Terms a(16) and beyond from _Andrew Howroyd_, Sep 19 2018