Potts model partition functions for self-dual families of strip graphs

The q-state Potts model was considered on families of self-dual strip graph of the square lattice of width and arbitrary great length with periodic boundary conditions. The general coefficients in terms of Chebyshev polynomials, the number of terms with each type of coefficient and the total number of terms were determined in the arbitrary square lattice of width. The ground state degeneracy per site was calculated in the limit of infinite length.