Cryptarithms are a type of mathematical puzzle in which the digits are replaced bye symbols (typically letters of the alphabet). For example: 9567 + 1085 = 10652 can be represented like this: abcd + efgb = efcbh The term alphametic is used when the letters from words and phrases. Here’s a famous one:

There is also a subset of alphametics called ‘doubly-true’ where the words are spelt out numbers which also from a valid sum: F O R T Y + T E N +T E N= S I X T Y | 2 9 7 8 6 + 8 5 0 + 8 5 0 = 3 1 4 8 6
Links to other cryptarithm sites:
- Jorge Soares’s Cryptarithms.
- The Contest Center.
- Alphametic Puzzle Generator.
- Alphametic Puzzle Solver.


