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2020 AMC 12B Question 24

AMC12 · 2020 AMC 12B

Question 24

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 $k \ge 1,$ 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 $3 \cdot 2,$ so $D(6) = 3.$ What is $D(96)?$
  1. $112$
  2. $128$
  3. $144$
  4. $172$
  5. $184$