Hello
a=1.03;
h=(a^200-a^20)/9;
ypoints=a^(20):h:a^200;
xpoints=log(ypoints)./log(a);
figure(1)
close(1)
figure(1)
hold on
axis([0 220 -1 1])
plot([20 200],[0 0],'b-','linewidth',3)
z=0.05;
for k=1:10
plot([xpoints(k) xpoints(k)],z*[-1 1],'b','linewidth',2)
end
text(20-1,-1.5*z,'20')
text(200-2,-1.5*z,'200')