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A007859 Number of matchings in rooted plane trees on n nodes. 0
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 June 7 00:18 EDT 2024. Contains 373138 sequences. (Running on oeis4.)