Now do Exercise 3.6. To emphasize that your rewrite is a more efficient
version of sum-of-divisors, call your procedure
sum-of-divisors-eff.
Time the search for perfect number
8128 by running:
(time (first-perfect-after-eff 496))
This test is also included in lab03-test.scm. Note that it calls
first-perfect-after-eff. It is defined in lab03.scm to
call perfect-eff?, which calls your sum-of-divisors-eff.
If you wrote sum-of-divisors-eff correctly, you will see a
significant improvement in search time. Finding 8128 should take
no more than half a second (500 milliseconds) on a modern desktop or laptop.