# Pseudo-random number

A

**pseudo-random number** is a number belonging to a sequence which appears to be

random, but can in fact be generated by a finite computation. They are used extensively in

computer science in places where randomness is essential to some application, but cannot be generated due to computation being

deterministic. See

Pseudorandom number generators.

The qualities which are required of a pseudo-random sequence of (binary) numbers -- if it is to be used in any application where apparent randomness is important -- are as follows:

- a sequence of
*n>1* 0s should occur half as often as a sequence of *n-1* 0s, and as often as *n* 1s

Various examples of

pseudorandom number generators exist, such as linear congruential generators, inversive generators etc.