Alphametics, first published in their modern form by

H. E. Dudeney in 1924, are a subset of

word/

math puzzles known as

cryptarithmetic puzzles presented in the form of a

sum. A

solution is the corresponding

integers which should replace the letters to make the

sum true.

Consider Dudeney's puzzle:

SEND
+MORE
-----
MONEY

Solution:

9567 (D=7, E=5, M=1, N=6, O=0, R=8, S=9, Y=2)
+1085
-----
10652

These

puzzles must conform to the following rules:

- The leftmost letter can not be zero in any word (in the above example, S and M are not equal to zero).
- There must be a one-to-one mapping between letters and digits.

The most elegant alphametics have only one solution. More impressive alphametics still are those which are doubly-true -- consider this example, provided by Michael Keith on his web site:

SEVEN
SEVEN
+ SIX
-----
TWENTY

Check out Michael Keith's page for more: *http://members.aol.com/s6sj7gt/*