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!)
A320727 a(n) is the minimal number of perfect matchings of a graph with 2n vertices that contains exactly three disjoint perfect matchings. 0
3, 4, 5, 6, 6, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
COMMENTS
Take a cycle graph which has two perfect matchings (PM), and add one PM that is disjoint to it. The number of possible PMs one can add is given by A003436. One ends up with a set of three disjoint perfect matchings (where disjoint means that each edge is an element of maximally one PM), but the graph will have more PMs. This sequence describes the minimal number of PMs that such a graph can have.
LINKS
Ilya Bogdanov, Graphs with only disjoint perfect matchings, MathOverflow.
Mario Krenn, Xuemei Gu, Anton Zeilinger, Quantum experiments and graphs: Multiparty states as coherent superpositions of perfect matchings, Physical review letters, 119(24), 240403 (2017).
CROSSREFS
Cf. A003436.
Sequence in context: A198466 A212642 A159624 * A036288 A159077 A049267
KEYWORD
nonn,hard,more
AUTHOR
Mario Krenn, Oct 20 2018
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 02:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)