Find the minimum value of
where
is an integer such that the number of trailing zeroes of
is divisible by
( has trailing zeroes while has )
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Let f ( n ) = ( n + 2 ) ! × ( n + 0 ) ! × ( n + 1 ) ! × ( n + 4 ) !
The domain of this function is [ 0 , + ∞ )
So let's first check f ( 0 ) .
( n + 2 ) ! × ( n + 0 ) ! × ( n + 1 ) ! × ( n + 4 ) ! = ( 0 + 2 ) ! × ( 0 + 0 ) ! × ( 0 + 1 ) ! × ( 0 + 4 ) ! = 2 ! × 0 ! × 1 ! × 4 ! = 4 8
There are 0 trailing zeroes in 4 8 . And since 0 is divisible by 2 0 1 5 , the answer is 0