*v*is a*factor*of*m*if there exist two words*u*and*w*such that*m*=*u**v**w*,(1)

*v*is a factor of*m*of order*n*if there exist at least*n*couples (*u*_{1},*w*_{1}), ... (*u*_{n},*w*_{n}) pairwise different such that*m*=*u*_{1}*v**w*_{1}=^{ ... }=*u*_{n}*v**w*_{n}.(2)

- (1.1)
- Construct a deterministic finite automaton that recognizes this language. (Your answer can be in the form of a transition table).
- (1.2)
- Give a regular expression for this language.
- (1.2)
- Write a
`lex`input file that accepts this language.

2004-12-01