r= x^8 + x^7 - x^5 - x^4 - x^3 + x + 1 q= (x^16 + x^15 + 4*x^8 + x + 1) / 4 P= x^8 + x^7 - 8*x^6 - 7*x^5 + 20*x^4 + 14*x^3 - 16*x^2 - 7*x + 6 v= x+1/x