Determine the maximum value of m3+n3m^3 + n^3m3+n3, where mmm and nnn are integers satisfying m,n∈{1,2,…,1981}m, n \in \{1, 2, \ldots, 1981\}m,n∈{1,2,…,1981} and (n2−mn−m2)2=1(n^2 - mn - m^2)^2 = 1(n2−mn−m2)2=1.