Let h be a harmonic function on Rn, n ≧ 2. Then there exists
on entire function f on C such that f(u) = h(u, 0, ...., 0) for all real
u.This fact has been used to deduce theorems for harmonic function
on Rn from classical results about entire functions. Moreover, we have
considered the characterizations of lower order and lower type of h in
terms of coefficients and ratio of these successive coefficients occurring
in power series expansion of f.