A sequence of Real Numbers is equidistributed if the probability of finding in any subinterval is proportional to the subinterval length.
See also Weyl's Criterion
References
Kuipers, L. and Niederreiter, H. Uniform Distribution of Sequences. New York: Wiley, 1974.
Pólya, G. and Szegö, G. Problems and Theorems in Analysis I. New York: Springer-Verlag, p. 88, 1972.
Vardi, I. Computational Recreations in Mathematica. Reading, MA: Addison-Wesley, pp. 155-156, 1991.