411856525348domain: NAppears in sequencesa(0) = -1, a(1) = 2; a(n) = 2*a(n-1) + a(n-2).at n=31A078343a(n) = 6*a(n - 1) - a(n - 2) with a(0) = 2, a(1) = 8.at n=15A266507