Petersen family (nonfiction): Difference between revisions

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[[File:Petersen_family.png|thumb|The Petersen family, a family of seven graphs reachable from the complete graph K6 and the Petersen graph by Δ-Y and Y-Δ transforms.]]In graph theory, a branch of [[Mathematics (nonfiction)|mathematics]], the '''Petersen family''' is a set of seven undirected graphs that includes the Petersen graph and the complete graph K6.
[[File:Petersen_family.png|thumb|The Petersen family, a family of seven graphs reachable from the complete graph K6 and the Petersen graph by Δ-Y and Y-Δ transforms.]]In [[Graph theory (nonfiction)|graph theory]], the '''Petersen family''' is a set of seven undirected graphs that includes the Petersen graph and the complete graph K6.


The Petersen family is named after Danish mathematician [[Julius Petersen (nonfiction)|Julius Petersen]].
The Petersen family is named after Danish mathematician [[Julius Petersen (nonfiction)|Julius Petersen]].
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== Fiction cross-reference ==
== Fiction cross-reference ==
* [[Gnomon algorithm]]
* [[Mathematics]]


== Nonfiction cross-reference ==
== Nonfiction cross-reference ==


* [[Julius Petersen (nonfiction)]]
* [[Julius Petersen (nonfiction)]]
* [[Graph theory (nonfiction)]]
* [[Mathematics (nonfiction)]]
* [[Mathematics (nonfiction)]]


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[[Category:Nonfiction (nonfiction)]]
[[Category:Nonfiction (nonfiction)]]
[[Category:Graph theory (nonfiction)]]
[[Category:Mathematics (nonfiction)]]
[[Category:Mathematics (nonfiction)]]

Latest revision as of 18:59, 8 December 2017

The Petersen family, a family of seven graphs reachable from the complete graph K6 and the Petersen graph by Δ-Y and Y-Δ transforms.

In graph theory, the Petersen family is a set of seven undirected graphs that includes the Petersen graph and the complete graph K6.

The Petersen family is named after Danish mathematician Julius Petersen.

Any of the graphs in the Petersen family can be transformed into any other graph in the family by Δ-Y or Y-Δ transforms, operations in which a triangle is replaced by a degree-three vertex or vice versa. These seven graphs form the forbidden minors for linklessly embeddable graphs, graphs that can be embedded into three-dimensional space in such a way that no two cycles in the graph are linked. They are also among the forbidden minors for the YΔY-reducible graphs.

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Fiction cross-reference

Nonfiction cross-reference

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