9795518464domain: NAppears in sequencesa(n) = (6^n - (-2)^n)/8.at n=14A053524Number of Eulerian cycles in the graph Cartesian product of C_n and a double edge.at n=11A298198a(n) = p(1,n), where p(x,n) is the strong divisibility sequence of polynomials based on sqrt(3) as in A327321.at n=13A329009