An interesting bit on the computational complexity of solving this problem (with a slightly different scoring function): http://cstheory.stackexchange.com/ques

An interesting bit on the computational complexity of solving this problem (with a slightly different scoring function): http://cstheory.stackexchange.com/questions/1854/is-finding-the-minimum-regular-expression-an-np-complete-problem http://cstheory.stackexchange.com/questions/1854/is-finding-...