Block Companion Singer Cycles, Primitive Recursive Vector Sequences, and   Coprime Polynomial Pairs over Finite Fields
  We discuss a conjecture concerning the enumeration of nonsingular matrices over a finite field that are block companion and whose order is the maximum possible in the corresponding general linear group. A special case is proved using some recent results on the probability that a pair of polynomials with coefficients in a finite field is coprime. Connection with an older problem of Niederreiter about the number of splitting subspaces of a given dimension are outlined and an asymptotic version of the conjectural formula is established. Some applications to the enumeration of nonsingular Toeplitz matrices of a given size over a finite field are also discussed. 
Sudhir R. Ghorpade and Samrith Ram
math.CO cs.IT math.IT