A generalized lucas sequence and permutation binomials

Let p be an odd prime and q = pm. Let l be an odd positive integer. Let p = -1 (mod l) or p = 1 (mod l) and l | m. By employing the integer sequence a(n) = (t=1)Sigma(l-1/2) (2 cos (pi(2t-1)) / (l))(n), which can be considered as a generalized Lucas sequence, we construct all the permutation binomials P(x) = x(r) + x(u) of the finite field F-q.