The number of onto functions $f$ from $\{1, 2, 3, …, 20\}$ only $\{1, 2, 3, …, 20\}$ such that $f(k)$ is a multiple of $3$, whenever $k$ is a multiple of $4$, is
The number of onto functions $f$ from $\{1, 2, 3, …, 20\}$ only $\{1, 2, 3, …, 20\}$ such that $f(k)$ is a multiple of $3$, whenever $k$ is a multiple of $4$, is
- [JEE MAIN 2019]
- A
${6^5} \times \left( {15} \right)!$
- B
$5! \times 6!$
- C
$\left( {15} \right)! \times 6!$
- D
${5^6} \times 15$
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- [IIT 1994]
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