def problem468():
    """


    An integer is called B-smooth if none of its prime factors is greater than
       B.

       Let S[B](n) be the largest B-smooth divisor of n.
       Examples:
       S[1](10) = 1
       S[4](2100) = 12
       S[17](2496144) = 5712

       Define F(n) = ∑[1≤B≤n] ∑[0≤r≤n] S[B](C(n,r)). Here, C(n,r) denotes the
       binomial coefficient.
       Examples:
       F(11) = 3132
       F(1 111) mod 1 000 000 993 = 706036312
       F(111 111) mod 1 000 000 993 = 22156169

       Find F(11 111 111) mod 1 000 000 993.
    """

    pass
