Discrete & Computational Geometry

, Volume 39, Issue 4, pp 786–790 | Cite as

There Are Integral Heptagons, no Three Points on a Line, no Four on a Circle

  • Tobias KreiselEmail author
  • Sascha Kurz


We give two configurations of seven points in the plane, no three points in a line, no four points on a circle with pairwise integral distances. This answers a famous question of Paul Erdős.


Integral distances Exhaustive search Orderly generation Solution to an Erdős problem 


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  1. 1.Department of MathematicsUniversity of BayreuthBayreuthGermany

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