function y=lliatq(x);
n=length(x);
lx=log(x);
ly=zeros(4*n,1);
for i=1:4:4*n;
  ly(i,1)=lx((i+3)/4);
end;
for i=1:3;
  for j=i+1:4:4*n-3;
    ly(j,1)=ly(j-i,1)*(4-i)/4 + ly(j-i+4,1)*i/4;
  end;
end;
beta=ols([ones(10,1),time(10)],ly(4*n-12:4*n-3,1));
ly(4*n-2:4*n,1)=beta(1)+beta(2)*[11;12;13];
y=exp(ly);
