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PROJECT EULER · #0474

Last Digits of Divisors

Statement only · UnsolvedOriginal problem ↗

For a positive integer n and digits d, we define F(n,d) as the number of the divisors of n whose last digits equal d.
For example, F(84,4)=3. Among the divisors of 84 (1,2,3,4,6,7,12,14,21,28,42,84), three of them (4,14,84) have the last digit 4.

We can also verify that F(12!,12)=11 and F(50!,123)=17888.

Find F(106!,65432) modulo (1016+61).

Write-up coming later

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