-2209943domain: ZAppears in sequencesa(0)=1, a(1)=1; thereafter a(n) = -a(n-1) - 2*a(n-2).at n=41A169998Expansion of (2 + x + x^2 + x^3 - x^4 - 2*x^5 - 4*x^6 - 8*x^7) / (1 - x^4 + 16*x^8) in powers of x.at n=43A247487a(n) = 3*a(n-1) - 4*a(n-2) with a(0) = a(1) = 1.at n=21A247560