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A136796 Number of labeled marked rooted trees with n nodes. 3
2, 16, 288, 8192, 320000, 15925248, 963780608, 68719476736, 5642219814912, 524288000000000, 54394721876836352, 6232805962420322304, 781754012972500385792, 106530593546206374264832, 15672832819200000000000000, 2475880078570760549798248448 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A marked rooted tree is a rooted tree where each node and edge is marked as + or -.

REFERENCES

F. Bergeron, G. Labelle and P. Leroux, Combinatorial Species and Tree-Like Structures, Cambridge, 1998, p. 293 (4.1.60).

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..200

Index entries for sequences related to rooted trees

FORMULA

E.g.f.: B(4*x)/2 where B(x) is e.g.f. of A000169.

a(n) = A052764(n)*2.

a(n) = 2^(2*n-1) * n^(n-1). - Vaclav Kotesovec, Mar 29 2014

MATHEMATICA

Table[2^(2*n-1)*n^(n-1), {n, 1, 20}] (* Vaclav Kotesovec, Mar 29 2014 *)

PROG

(MAGMA) [2^(2*n-1)*n^(n-1): n in [1..20]]; // Vincenzo Librandi, Mar 29 2014

CROSSREFS

Cf. A136794 (unlabeled version), A136797 (tree version).

Sequence in context: A227674 A102599 A123744 * A055546 A009549 A254744

Adjacent sequences:  A136793 A136794 A136795 * A136797 A136798 A136799

KEYWORD

nonn

AUTHOR

Christian G. Bower, Jan 21 2008

EXTENSIONS

More terms from Vincenzo Librandi, Mar 29 2014

STATUS

approved

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Last modified October 17 01:24 EDT 2018. Contains 316275 sequences. (Running on oeis4.)