Concyclic
Four or more points 
, 
, 
, 
, ... which lie on a Circle 
are said to be concyclic. Threepoints are trivially concyclic since three noncollinear points determine a Circle. The number of the 
Lattice Points 
which can be picked with no four concyclic is 
(Guy 1994).
A theorem states that if any four consecutive points of a Polygon are not concyclic, then its Area canbe increased by making them concyclic. This fact arises in some Proofs that the solution tothe Isoperimetric Problem is the Circle.
See also Circle, Collinear, Concentric, Cyclic Hexagon, Cyclic Pentagon, Cyclic Quadrilateral,Eccentric, N-Cluster
References
Guy, R. K. ``Lattice Points, No Four on a Circle.'' §F3 in Unsolved Problems in Number Theory, 2nd ed. New York: Springer-Verlag, p. 241, 1994.
- Affine Complex Plane
- Affine Connection
- Affine Equation
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- Airy Differential Equation
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- Aitken Interpolation
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