login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A055540 Total number of leaves (nodes of vertex degree 1) in all graphs of n nodes. 4
0, 2, 4, 14, 38, 153, 766, 6259, 88064, 2324157, 116563882, 11060411527, 1968703079886, 654492092481733, 406111248305672980, 471005105043787823717, 1023566652048387537072658, 4179937690541808658135640875, 32172436158252943170541450460638 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..50

Eric Weisstein's World of Mathematics, Tree Leaf

FORMULA

a(n) = Sum_{k=1..n} k*A327371(n, k). - Andrew Howroyd, Sep 04 2019

PROG

(PARI) \\ See A327371 for G.

seq(n)=Vec(subst(deriv(G(n), y), y, 1), -n) \\ Andrew Howroyd, Jan 22 2021

CROSSREFS

Cf. A003227, A003228, A055541, A327371.

Sequence in context: A053623 A035010 A349450 * A006252 A079995 A279322

Adjacent sequences:  A055537 A055538 A055539 * A055541 A055542 A055543

KEYWORD

nonn

AUTHOR

Eric W. Weisstein

EXTENSIONS

a(8) and a(9) from Eric W. Weisstein, Jun 02 2004

a(10) from Andrew Howroyd, Sep 04 2019

Terms a(11) and beyond from Andrew Howroyd, Jan 22 2021

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 25 16:01 EST 2022. Contains 350572 sequences. (Running on oeis4.)