Recognizing Numerical Constants

The advent of inexpensive, high-performance computers and new efficient algorithms have made possible the automatic recognition of numerically computed constants. In other words, techniques now exist for determining, within certain limits, whether a computed real or complex number can be written as a simple expression involving the classical constants of mathematics. These techniques will be illustrated by discussing the recognition of Euler sum constants, and also the discovery of new formulas for π and other constants, formulas that permit individual digits to be extracted from their expansions. Bailey: NASA Ames Research Center, Mail Stop T27A-1, Moffett Field, CA 94035-1000, USA; [email protected]. Plouffe: Department of Mathematics and Statistics, Simon Fraser University, Burnaby, BC V5A 1S6, Canada; [email protected].