This is documentation for Mathematica 7, which was
based on an earlier version of the Wolfram Language.
 Number Recognition A core activity in exploratory experimental mathematics is recognition of numbers: going backward from a number to find out how it can be generated. Mathematica provides tools for recognizing many classes of numbers, including a number of original algorithms. Element — test whether a number is in a given class      Rationalize — find a rational approximation      RootApproximant — find an approximating algebraic number LatticeReduce — find reduced basis vectors in a lattice      FunctionExpand — reduce an exact numeric expression to simpler functions      PrimeQ — recognize prime numbers      FindSequenceFunction — find functional forms for integer sequences TUTORIALS Types of Numbers Algebraic Numbers Algebraic Number Fields Integer and Number Theoretic Functions Simplifying with Assumptions MORE ABOUT Continued Fractions Number Digits Number Theory Analyzing Integer Data Integer Sequences RELATED LINKS Demonstrations related to Number Recognition (The Wolfram Demonstrations Project)