From: Martin Ankerl Date: 2005-04-11T17:39:36+09:00 Subject: Re: Translating A Pattern of Data Into Equation, and ultimately code > Gotit! Try letter xor column :) Wow, very good! I could not figure this out myself. Here is the very simple formula: def encode(letter, column) (letter-?a + 1)^column end encode(?z, 1) encode(?a, 2) encode(?c, 3) encode(?h, 4) gives the correct result. martinus