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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Fri, 6 Mar 2015 00:10:06 -0700
Subject: Re: Speeding up permutations generation
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Xref: csiph.com comp.lang.python:86994

On Thu, Mar 5, 2015 at 11:44 PM, Abhiram R <abhi.darkness@gmail.com> wrote:
> Hi all,
> Is there a way to generate permutations of large arrays of sizes say,in the
> hundreds, faster than in the time itertools.permutations() can return?

A list of 100 elements has approximately 9.33 x 10**157 permutations.
If you could somehow generate one permutation every yoctosecond,
exhausting them would still take more than a hundred orders of
magnitude longer than the age of the universe.