function [A,b,xref]=fredholm(m)
  a=0.3;
  ns=5;
  p=linspace(0,2*pi,m+1)';
  p=p(1:m);
  z=(1+a*cos(ns*p)).*exp(i*p);
  zp=(i-ns*a*sin(ns*p)+i*a*cos(ns*p)).*exp(i*p);
  zpp=-(1+(1+ns*ns)*a*cos(ns*p)+2*i*ns*a*sin(ns*p)).*exp(i*p);
  w=2/m;
  b=cos(p);
  A=diag(1+w/2*imag(zpp./zp));
  for k=1:m
    A(1:k-1,k)=imag(w*zp(k)./(z(k)-z(1:k-1)));
    A(k+1:m,k)=imag(w*zp(k)./(z(k)-z(k+1:m)));     
  end
  xref=A\b;
  b=A*xref;