function cheb(n)

a = -5:1/100:5;
eval_f = 1./(1.+a.^2);

% equally spaced nodes
x=-5:10/(n-1):5;
y=1./(1.+x.^2);

p=polyfit(x,y,n-1);
b=polyval(p,a);

equally_spaced = max(abs(b-eval_f))

% Chebyshev-nodes:
x=cheb_nodes(-5,5,n);
y=1./(1.+x.^2);

p=polyfit(x,y,n-1);
b=polyval(p,a);

chebyshev = max(abs(b-eval_f))