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A045722 Number of border edges in all noncrossing rooted trees on n nodes. 1

%I

%S 1,6,28,150,858,5096,31008,191862,1201750,7597590,48384180,309939240,

%T 1994981688,12892738800,83604224384,543722433078,3545056580814,

%U 23164787710610,151662849838500,994674967479270,6533629880128890

%N Number of border edges in all noncrossing rooted trees on n nodes.

%H <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a>

%F a(n) = n*binomial(3n-5, n-2)/(n-1) for n >= 2.

%F G.f.: (1+g-7*g^2+3*g^3)/((1-3*g)*(g-1)^2) where g*(1-g)^2 = x. - _Mark van Hoeij_, Nov 10 2011

%Y Cf. A026004.

%K nonn

%O 1,2

%A _Emeric Deutsch_

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Last modified September 27 19:04 EDT 2020. Contains 337388 sequences. (Running on oeis4.)