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PROJECT EULER · #0468

Smooth Divisors of Binomial Coefficients

Statement only · UnsolvedOriginal problem ↗

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

Let SB(n) be the largest B-smooth divisor of n.
Examples:
S1(10)=1
S4(2100)=12
S17(2496144)=5712

Define F(n)=B=1nr=0nSB((nr)). Here, (nr) denotes the binomial coefficient.
Examples:
F(11)=3132
F(1111)mod1000000993=706036312
F(111111)mod1000000993=22156169

Find F(11111111)mod1000000993.

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