Dr. Dobb's Python-URL! - weekly Python news and links (Mar 17)

Tim Peters tim.one at comcast.net
Wed Mar 19 21:26:56 CET 2003

[Robin Becker]
> I assume absolute normality excludes the case where one expresses the
> number in itself as a base or am I being more than usually stupid.

It has to do with digit distribution in conventional positional notation in
positive integer bases (>= 2).  Google will lead you to a precise definition
faster than I can regurgitate one.

> Also I suppose that being non-random implies finiteness (in some sense)
> so are we just talking 'symbol' count or information.

Sorry, I couldn't parse that -- but digits is digits, and the requirement
that all k-digit subsequences appear equally often, for each k >= 1, is
intuitively simple.  See Knuth (Volume 2) for an entertaining argument that
piles on more intuitive requirements, until he ends up with a definition for
randomness that (it turns out) no number can meet!  Intuition isn't always
enough -- or maybe it is, and randomness doesn't exist.

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