login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Today, Nov 11 2014, is the 4th anniversary of the launch of the new OEIS web site. 70,000 sequences have been added in these four years, all edited by volunteers. Please make a donation (tax deductible in the US) to help keep the OEIS running.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A106363 Planar trees where no branch is identical to its adjacent neighbor. 2
1, 1, 0, 1, 0, 1, 3, 7, 14, 43, 115, 326, 931, 2719, 7979, 23804, 71418, 216444, 660276, 2028558, 6268350, 19479746, 60835542, 190881085, 601459251, 1902680249, 6040955223, 19245061851, 61503863732, 197135868680, 633615135842 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

Table of n, a(n) for n=1..31.

Index entries for sequences related to trees

FORMULA

G.f.: A(x) = B(x) + (C(x^2) - C(x)^2)/2. B(x) is g.f. of A106362. C(x) is g.f. of A106361.

CROSSREFS

Cf. A002995.

Sequence in context: A146936 A184264 A146155 * A128658 A234042 A001203

Adjacent sequences:  A106360 A106361 A106362 * A106364 A106365 A106366

KEYWORD

nonn

AUTHOR

Christian G. Bower, Apr 29 2005

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified November 26 03:41 EST 2014. Contains 250017 sequences.