

A101488


Number of naturally embedded binary trees with n nodes that have no label greater than 0.


1



1, 1, 1, 2, 4, 10, 26, 73, 213, 645, 2007, 6391, 20741, 68407, 228753, 774162, 2647548, 9138342, 31802118, 111489492, 393442848, 1396771812, 4985732628, 17884908282, 64449398994, 233220788850, 847211744806, 3088649627798
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OFFSET

0,4


LINKS



FORMULA

G.f.: ((14z)^(3/2)1+8z2z^2)/(2z(1+z)).


MATHEMATICA

CoefficientList[((14z)^(3/2)1+8z2z^2)/(2z(1+z)) + O[z]^28, z] (* JeanFrançois Alcover, Jul 25 2018 *)


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



