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A007859 Number of matchings in rooted plane trees on n nodes. 1
0, 1, 4, 18, 84, 405, 2002, 10101, 51844, 269994, 1423784, 7590044, 40846390, 221650195, 1211606190 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

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

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

Index entries for sequences related to rooted trees

CROSSREFS

Sequence in context: A151251 A293490 A010849 * A185132 A085923 A110166

Adjacent sequences:  A007856 A007857 A007858 * A007860 A007861 A007862

KEYWORD

nonn,more

AUTHOR

Martin Klazar

STATUS

approved

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Last modified January 18 01:05 EST 2020. Contains 330995 sequences. (Running on oeis4.)