nmax = 50;
a = 3.5;
x = 0.2 * ones(nmax,1);

for n = 1: nmax - 1 do
 x(n+1) = a * x(n) * (1.0 - x(n));
end

plot(x,'o-r');
xlabel("n");
ylabel("X(n)");

plot([0,0],[0,1]);