PRandom = function(low, high, repeats) {
    Pattern.call(this);
    this.low = low;
    this.high = high;
    this.repeats = repeats;
    this.position = 0;
}
Sequence of random numbers.

@constructor
@extends Pattern
@param {Number|Pattern} low Lowest possible value.
@param {Number|Pattern} high Highest possible value.
@param {Number} repeats Number of values to generate.