Bobo has a sequence of integers s1, s2, ..., sn where 1 ≤ si ≤ k.Find out the number of distinct sequences modulo after removing exactly m elements.
Bobo has a sequence of integers s1, s2, ..., sn where 1 ≤ si ≤ k. Find out the number of distinct sequences modulo (109+7) after removing exactly m elements.
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