# Petersen graph

> English word · Noun

## Definitions
1. An undirected graph with 10 vertices and 15 edges, serving as a simple example and counterexample for many problems in graph theory.

## Etymology
Named after Julius Petersen, who in 1898 constructed it to be the smallest bridgeless cubic graph with no three-edge-coloring.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/petersen-graph