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A036252 Number of trees with 3-colored leaves. 0
1, 3, 6, 6, 16, 39, 114, 335, 1081, 3574, 12408, 44076, 160915, 598244, 2263400, 8681464, 33713947, 132305267, 524095596, 2093208435, 8422013745, 34110403728, 138979989162, 569339728312, 2343898451275, 9693334574919 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..25.

Index entries for sequences related to trees

FORMULA

G.f.: A(x) = B(x)+B(x)^2/2+B(x^2)/2-B(x)*(B(x)-2*x), where B(x) = g.f. for A029857.

CROSSREFS

Sequence in context: A107972 A238775 A269525 * A103463 A265026 A304335

Adjacent sequences:  A036249 A036250 A036251 * A036253 A036254 A036255

KEYWORD

nonn

AUTHOR

Christian G. Bower, Nov 15 1998.

STATUS

approved

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Last modified November 21 16:04 EST 2019. Contains 329371 sequences. (Running on oeis4.)