0,3

Index entries for sequences related to trees

G.f.: (1-x)(2-x-x^2) - (2-x+x^2)\sqrt{1-2x-x^2} \over 3 x^3.

Sequence in context: A125222 A136168 A120015 this_sequence A166883 A145158 A132070

Adjacent sequences: A003689 A003690 A003691 this_sequence A003693 A003694 A003695

nonn

apost(AT)math.mit.edu (Alex Postnikov)