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Re: puzzle with string permutations [photo]

From: Emanuel Berg
Subject: Re: puzzle with string permutations [photo]
Date: Tue, 07 Jun 2022 16:18:43 +0200
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux)

> to do it without counting I think the formula is
>   n!/(n - r)!
> where n is the size of the set - here 26, as
>   (length (alphabet t)) ; 26
> and r is the number of items to be picked and arranged, or
> here the length of the word.

It doesn't work exactly like that with strings, since for
example the scrambled word "ogod" is actually, here, treated

  o_1 g o_2 d

Yet the words

  g o_1 o_2 d 
  g o_2 o_1 d

are duplicates.

So the n, the set or alphabet is A = { d g o }

Yet it's stipulated that o, and only o, must be used twice!

Maybe there is a formula for that as well! Divide by 2 for all
chars that appear twice? But then how to generalize so it
scales for chars that appear thrice and so on?

The truth is out there ...

underground experts united

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