```Date: Jun 27, 2013 4:56 PM
Author: Rudolf Licht
Subject: Simple Math/Logic Problem

I'm trying to figure out the math/logic on this programming problem I got.So I have a series of numbers and letters:Numbers: 1-6Letters: a, b, c, d, e, f, g, h, i, jThese are arranged in long patterns like so:a5b a1f a3g a3i b5f b4i c1d e6h e5j g3i g6j h4j i6jThe numbers are always in the middle. And the letters arealways in alphabetical order. So e5j and j5e would be equal for my purposes. Also they all are exactly 3 characters.So what I'm trying to do is match these strings against other similar strings, in a gradually decremental way. So take the above pattern as an example. I would try to match on all 13 points, after 12 then 11 etc. Even if they do match I still need to record all the matches down to like 2 or 3. Take the above example once it gets to like 9 points the possible combinations start to grow. But yeah  I don't understand the math governing this, or how to calculate the total possible combinations. If someone could point me in the right direction, also if you give me some esoteric math formula, I probably won't understand it.Thanks in advance.
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