r= x^16 + x^14 - x^10 - x^8 - x^6 + x^2 + 1 q= (x^22 +x^21 +x^20 -x^12 + 2*x^11 - x^10 + x^2 - 2*x + 1) / 3 P= 3*q_k20method66 v= x