101916domain: NAppears in sequencesa(n) is the smallest integer such that the sum of any three ordered terms a(k), k <= n, is unique.at n=33A051912a(1) = 1, a(2) = 9, a(n+2) = 9*a(n+1) + (n + 1)^2*a(n).at n=5A142982a(n) = A255470(2^n-1).at n=8A255471G.f. = Phi^3*F^3, where Phi = g.f. for A028930, F = g.f. for A028959.at n=19A328534