Ok, ive had my calculator out. I reckon that there are 26!/(26-3)! = 15,600 permutations of three letters (number of possible orders of 3 letters taken from the alphabet).
But then if you include the possiblity of repeating letters (aaa, aab, aac ...) then i think the total becomes 26*26*26 = 17,576. Surely not all of these permuatations are registered?!
just don't ask me to list them all!
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