def problem457():
    """


    Let f(n) = n^2 - 3n - 1.
       Let p be a prime.
       Let R(p) be the smallest positive integer n such that f(n) mod p^2 = 0 if
       such an integer n exists, otherwise R(p) = 0.

       Let SR(L) be &Sum;R(p) for all primes not exceeding L.

       Find SR(10^7).
    """

    pass
