One of the Plücker Characteristics, defined by

where is the class, the order, the number of nodes, the number of Cusps, the number of stationary tangents (Inflection Points), and the number of Bitangents.

**References**

Coolidge, J. L. *A Treatise on Algebraic Plane Curves.* New York: Dover, p. 100, 1959.

© 1996-9

1999-05-25