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A007856 Subtrees in rooted plane trees on n nodes. 0
1, 3, 12, 52, 236, 1109, 5366, 26639, 135300, 701269, 3700400, 19834973, 107784622, 592705377, 3292970302 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

M. Klazar, Twelve countings with rooted plane trees, European Journal of Combinatorics 18 (1997), 195-210; Addendum, 18 (1997), 739-740.

LINKS

Table of n, a(n) for n=1..15.

Index entries for sequences related to rooted trees

CROSSREFS

Sequence in context: A151192 A151193 A151194 * A151195 A151196 A010736

Adjacent sequences:  A007853 A007854 A007855 * A007857 A007858 A007859

KEYWORD

nonn

AUTHOR

Martin Klazar (klazar(AT)kam.mff.cuni.cz)

STATUS

approved

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Last modified December 20 01:21 EST 2014. Contains 252240 sequences.