static/files/articles/combinations-and-permutations/definitions.tex


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\begin{array}{|c|c|c|c|}
\hline
    \text{Denoted} &
    \text{Read As} &
    \text{Formula} & 
    \text{Example} \\
\hline
    n! &
    \text{"N factorial"} &
    n! = \prod_{i=1}^n{i} &
    5! = 1 \cdot 2 \cdot 3 \cdot 4 \cdot 5 = 120 \\
\hline
    {n \choose k} &
    \text{"N choose K"} &
    {n \choose k} = \frac{n!}{k!(n - k)!} &
    {5 \choose 3} = \frac{5!}{3!(5 - 3)!} = 10\\
\hline
\end{array}