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Algebra Difficulty 8.2 Shortlist Find the answer

For a given positive integer nn and prime number pp, find the minimum value of positive integer mm that satisfies the following property: for any polynomial f(x)=(x+a1)(x+a2)(x+an)f(x)=(x+a_1)(x+a_2)\ldots(x+a_n) (a1,a2,,ana_1,a_2,\ldots,a_n are positive integers), and for any non-negative integer kk, there exists a non-negative integer kk' such that vp(f(k))<vp(f(k))vp(f(k))+m.v_p(f(k))<v_p(f(k'))\leq v_p(f(k))+m. Note: for non-zero integer NN,vp(N)v_p(N) is the largest non-zero integer tt that satisfies ptNp^t\mid N.

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Solution

For a given positive integer n n and prime number p p , we aim to find the minimum value of the positive integer m m that satisfies the following property: for any polynomial
f(x)=(x+a1)(x+a2)(x+an) f(x) = (x + a_1)(x + a_2) \ldots (x + a_n)
where a1,a2,,an a_1, a_2, \ldots, a_n are positive integers, and for any non-negative integer k k , there exists a non-negative integer k k' such that
vp(f(k))<vp(f(k))vp(f(k))+m. v_p(f(k)) < v_p(f(k')) \leq v_p(f(k)) + m.
Here, vp(N) v_p(N) denotes the largest non-negative integer t t such that ptN p^t \mid N for a non-zero integer N N .

The minimum value of m m that satisfies this property is:
n+vp(n!). n + v_p(n!).

The answer is: \boxed{n + v_p(n!)}.

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