43112258domain: NAppears in sequencesa(n) = 1^n + 2^n + 3^n.at n=16A001550a(n) = 1^n + 4^n + 9^n.at n=8A074515a(n) = (-1)^n + (-2)^n + 3^n (-1, -2 and 3 are the roots of the equation x^3 = 7*x + 6).at n=16A135399