format long
x=[0.3 0.4 0.5 0.6];
e=[0.5488 0.4493 0.3679 0.3012];
y=e-x;
n=size(x)(2)-1;
Q=zeros(n+1);
Q(:,1)=x';
z=0;

for i=1:n
  for j=1:i
    Q(i+1,j+1)=((z-y(i-j+1))*Q(i+1,j)-(z-y(i+1))*Q(i,j))/(y(i+1)-y(i-j+1));
  end
end
Q(n+1,n+1)