Sudoku Algorithm

Sudoku is a puzzle that requires human reasoning and logic to solve.  These puzzles can also be solved by computers using similar logic techniques and brute force trying of different combinations.  There is not currently an efficient algorithm to solve this type of problem with a gauranteed solution without trying a huge number of combinations.  This puzzle is part of a special class of problems including scheduling, network routing, and gene sequencing [1].  Scientists and mathematicians are very interested in finding an algorithm for these types of problems [1].  Some scientists believe that none exists [1].

[1] Aaronson, Lauren. February 2006. "Sudoku Science." IEEE Spectrum.