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Topic: unique ordering
Replies: 9   Last Post: May 10, 2014 1:16 PM

 Messages: [ Previous | Next ]
 scattered Posts: 92 Registered: 6/21/12
Re: unique ordering
Posted: May 10, 2014 10:42 AM

On Saturday, May 10, 2014 10:07:55 AM UTC-4, G. A. Edgar wrote:
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> > Thought experiment:
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> >
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> > Lets say that I randomly draw N letters out of a Scrabble letter-bag. I will
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> > then place those letters in a horizontal line on a table. How many UNIQUE
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> > patterns of letters can I produce? If there were no duplicates it would be
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> > easy (N factorial) but when there are duplicate letters it seems more
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> > complicated.
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> >
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> > Bob
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> Are you thinking of actual Scrabble? Some letters have duplicates, and
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> other don't? And the number of duplicates varies on how
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> frequently-used the letter is?
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> Or is this a mathematical Scrabble: Every letter has an unlimited
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> supply, and the probability of drawing an E doesn't depend on whether
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> some E's have already been drawn.
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> --
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> G. A. Edgar http://www.math.ohio-state.edu/~edgar/

I took OP as asking about actual scrabble. The mathematical scrabble question
that you alluded to is also quite interesting.

Professor Edgar, I find it an honor sharing a thread with you. 20+ years ago when I was writing my dissertation two of your early papers were quite helpful. The papers were:

"The class of topological spaces is equationally definable"

and

"A cartesian closed category for topology"

So -- thanks!

-scattered

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