Algebraic continued fractions in F_q((T^{-1})) and recurrent sequences   in F_q
  There exists a particular subset of algebraic power series over a finite field which, for different reasons, can be compared to the subset of quadratic real numbers. The continued fraction expansion for these elements, called hyperquadratic, can sometimes be made explicit. Here we describe this expansion for a wide family of hyperquadratic power series in odd characteristic. This leads to consider interesting recurrent sequences in the finite base field when it is not a prime field. 
Alain Lasjaunias