computing eccentric, total eccentricity connectivity polynomial and hosoya polynomial of unitary cayley graphs

For a positive integer n > 1, the unitary cayley graph x_n is the graph whose vertex set is zn, the integers modulo n and two vertices x, y are adjacent if and only if gcd(x − y, n) = 1. x_n is vertex-transitive and regular of degree φ(n), where φ denotes the euler totient function. in this paper the the eccentric connectivity polynomial and hosoyapolynomial of xn is computed.