function overtune(c, s)
% Play the basic freq c with the strengths of the 1st, 2nd, ..., 5th overtune combinded for 1 second
% s=[s1, s2, s3, s4, s5] stands for the relative strengths of each overtune, usually s(1)=1
Fs = 8192;
x=linspace(0,1,Fs);
y=s(1)*sin(2*c*pi*x);
for j=2:length(s)
    freq=j*c;
    y=y+s(j)*sin(2*freq*pi*x);
end
y=y/max(abs(y));
sound(y, Fs);