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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Ada.Numerics.Float_Random.Generator question
Date: Fri, 30 Sep 2016 20:59:14 -0700
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Date: 2016-09-30T20:59:14-07:00
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Robert Eachus <rieachus@comcast.net> writes:
>> aren't *all* PRNGs cyclic?
> No, a simple counter-example is a generator that uses the digits of
> pi.  The digits of any transcendental number will do. 

I don't see how this would work--to never cycle, it would need infinite
internal state.  You could consider the digits of pi to be part of the
state, but to count off the digits, you need a counter of infinite
width.

> But about how to implement it so that you don't have arbitrary pauses.

https://en.wikipedia.org/wiki/Spigot_algorithm