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2020 AMC 10B Question 25

AMC10 · 2020 AMC 10B

Question 25

Let $D(n)$ denote the number of ways of writing the positive integer $n$ as a product $$
n = f_1\cdot f_2\cdots f_k,
$$ where $k\ge1,$ the $f_i$ are integers strictly greater than $1,$ and the order in which the factors are listed matters (that is, two representations that differ only in the order of the factors are counted as distinct). For example, the number $6$ can be written as $6,$ $2\cdot 3,$ and $3\cdot2,$ so $D(6) = 3.$ What is $D(96)?$
  1. $112$
  2. $128$
  3. $144$
  4. $172$
  5. $184$