a(0) = 1, a(n+1) = 6*a(n)^3 - 3*a(n).A378683a(0) = 1, a(n+1) = 6*a(n)^3 - 3*a(n).Terms a(0) =1a(1) =3a(2) =153a(3) =21489003External referencesoeis: A378683