• Corpus ID: 14306390

Astral (n 4 ) Configurations

  title={Astral (n 4 ) Configurations},
  author={Branko Gr{\"u}nbaum}
A family of n points and n (straight) lines in the Euclidean plane is said to be an (n 4) configuration provided each point is on four of the lines and each line contains four of the points. A configuration may have various symmetries, that is, there may exist isometric mappings of the plane onto itself that map the configuration onto itself; all the symmetries of a configuration form its group of symmetries. It is obvious that no more than two points of a line can be in the same transitivity… 

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