N:=20;
X:=y^3 - x^3*y^2 - x^2*y + x;
q:=(x - y)/(x*y - 1);
t:= -4*x*(x-y)*(x*y-1)^2/(x^4*y^3 + 3*x^4*y - 10*x^3*y^2 - 2*x^3 + 4*x^2*y^3 + 8*x^2*y - 2*x*y^2 - 2*x - y^3 + y);
E:=[0,t^2-2*q*t-2,0,-(t^2-1)*(q*t+1)^2,0];
P:=[(t+1)*(q*t+1),t*(q*t+1)*(t+1)];