iran-konkur 2021 Q127

iran-konkur · Other · konkur-riazi_1400_specialized Not Maths
127- For every natural number $n$, we have $n! = 3^{a_1} \times 5^{a_2} \times \Delta^{a_3} \times \cdots$. The value of $\displaystyle\sum_{i=1}^{\infty} a_i$ for $n = 20$ is which of the following?
(1) $28$ (2) $32$ (3) $36$ (4) $40$
\textbf{127-} For every natural number $n$, we have $n! = 3^{a_1} \times 5^{a_2} \times \Delta^{a_3} \times \cdots$. The value of $\displaystyle\sum_{i=1}^{\infty} a_i$ for $n = 20$ is which of the following?

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(1) $28$ \hfill (2) $32$ \hfill (3) $36$ \hfill (4) $40$

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