%shows the difference between computing constants inside the loop verses
%outside the loop
n=10000000;
f=ones(1,n);

tic
for i=3:n
    f(i)=log(2)*(f(i-1)+f(i-2));
end
t1=toc


f=ones(1,n);

tic
a=log(2);
for i=3:n
    f(i)=a*(f(i-1)+f(i-2));
end
t2=toc