function A=Erato(n)
A=2:n;// n entier >=2.
k=1;
while A(k) <= sqrt(A($))
    Restes=A(k+1:taille(A))-A(k)*floor(A(k+1:taille(A))/A(k))
    I=find(Restes==0);
    if taille(I)>0
        A(k+I)=[];
    end;
    k=k+1;
end;
endfunction