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

 

Logo

Annual Appeal: Please make a donation (tax deductible in USA) to keep the OEIS running. Over 5000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A120412 Number of different graphs with n = number of vertices plus number of edges. 0
1, 1, 2, 2, 3, 5, 7, 10, 16, 25, 40, 66, 111 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Given two integers p, q, one can count the number of different graphs having p vertices and q edges by the standard Polya counting technique. Our sequence is then obtained by summing up the terms with p+q=n.

LINKS

Table of n, a(n) for n=1..13.

EXAMPLE

a(3) = 2 because there is a graph with 3 vertices and no edges and a graph with 2 vertices and one edge.

CROSSREFS

Sequence in context: A097333 A001083 A173696 * A022864 A039894 A133225

Adjacent sequences:  A120409 A120410 A120411 * A120413 A120414 A120415

KEYWORD

nonn

AUTHOR

Petr Vojtechovsky (petr(AT)math.du.edu), Jul 05 2006

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified December 4 21:33 EST 2016. Contains 278755 sequences.