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### Combinations of Lottery Numbers

Date: 5 Aug 1995 01:53:15 -0400
From: Anonymous
Subject: Lottery

I am in need of a quick way to display all the permutations for my state's
lottery. Our new lotto will start soon and the object is to pick 5 numbers,
1 through 39, with no repeat or bonus numbers.  How can I get a listing of
all 575,000+ possible ways to play?

reason I ask is that for almost (3) years the Texas lottery has never
drawn a winning play TWICE. That being the trend, it seems possible to
eliminate past drawings and focus only on UNDRAWN plays. Can you help or
advise how I can find resolution?  Thanks!

Date: 7 Aug 1995 09:53:02 -0400
From: Dr. Ethan
Subject: Re: Lottery

It's not clear that a listing is what you want.  If we put 1000 plays
on each page, the listing would be 576 pages long, and you'd get dizzy

I don't know how often the Texas lottery is drawn, but suppose it's once
per week.  In 3 years, that would eliminate 156 plays from consideration.
So if you assume the same play won't be drawn twice, it drops the number
of plays you have to consider from 575,757 to 575,601.  Which is to say,
it hardly makes any difference.

That is, if you just start choosing combinations randomly, the probability
that you'll repeat a previously winning play is about 1 in 3000.

So the best way to avoid previous winning plays is just to list those,
make your choices, and before committing to a choice, check it against
the list of previous winners.  That entails managing a list of a few
hundred previous winners, as opposed to a list of half a million
non-winners.

Hope that helps,

Ethan, Doctor On Call
Associated Topics:
High School Permutations and Combinations

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