8253297domain: NAppears in sequencesConstant term in the reduction by (x^2 -> x+1) of the polynomial p(n,x) given in Comments.at n=18A192872a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 1, a(2) = 1, a(3) = -1.at n=37A295671