a(n) = (6^n - 2^n)^2 / 16.A144843a(n) = (6^n - 2^n)^2 / 16.Terms a(0) =1a(1) =64a(2) =2704a(3) =102400a(4) =3748096a(5) =135675904a(6) =4893282304a(7) =176265625600External referencesoeis: A144843