137141domain: NAppears in sequencess(n+3)/2, where s is A024945.at n=19A024946a(n) = a(n-1) + 3*a(n-2) -2*a(n-3) - 2*a(n-4), where a(0) = -1, a(1) = 2, a(2) = 3, a(3) = 4.at n=23A295721