A number

where is an Integer or Rational Number, is the Inverse Tangent, and is the Inverse Cotangent. Gregory numbers arise in the determination of Machin-Like Formulas. Every Gregory number can be expressed uniquely as a sum of s where the s are Størmer Numbers.

**References**

Conway, J. H. and Guy, R. K. ``Gregory's Numbers'' In *The Book of Numbers.* New York:
Springer-Verlag, pp. 241-242, 1996.

© 1996-9

1999-05-25