login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A165452 Number of connected graphs of odd girth at least 7 with n vertices. 1
1, 1, 1, 3, 5, 17, 45, 184, 748, 4143, 26532, 221032, 2326853, 32202266, 589436301, 14459238676, 477812658943 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

The odd girth of a graph is the length of a shortest cycle of odd length. Thus, these are the connected graphs that do not have a triangle or C_5 as induced subgraph. - Falk Hüffner, Jan 15 2016

The bipartite graphs (which have no odd cycles) are included.

LINKS

Table of n, a(n) for n=1..17.

F. Hüffner, tinygraph, software for generating integer sequences based on graph properties, version ece94ef.

CROSSREFS

Cf. A005142, A024607.

Inverse EULER transform of A345247.

Sequence in context: A236458 A131342 A005142 * A106063 A215106 A006483

Adjacent sequences:  A165449 A165450 A165451 * A165453 A165454 A165455

KEYWORD

nonn

AUTHOR

Friedrich Regen (friedrich.regen(AT)tu-ilmenau.de), Sep 20 2009

EXTENSIONS

a(15) and a(16) added using tinygraph by Falk Hüffner, Jan 15 2016

a(17) added by Brendan McKay, Jun 12 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 September 21 07:28 EDT 2021. Contains 347596 sequences. (Running on oeis4.)