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%I #15 Apr 05 2019 10:00:20
%S 0,1,4,18,84,405,2002,10101,51844,269994,1423784,7590044,40846390,
%T 221650195,1211606190
%N Number of matchings in rooted plane trees on n nodes.
%H M. Klazar, <a href="http://dx.doi.org/10.1006/eujc.1995.0095">Twelve countings with rooted plane trees</a>, European Journal of Combinatorics 18 (1997), 195-210; Addendum, 18 (1997), 739-740.
%H <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a>
%K nonn,more
%O 1,3
%A _Martin Klazar_