ordered pair (n,r)

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jagdish
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ordered pair (n,r)

Unread post by jagdish » Tue Jun 21, 2016 5:42 pm

Total number of whole number integer ordered pair $(n,r)$ in $\displaystyle \binom{n}{r} = 120$
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asif e elahi
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Re: ordered pair (n,r)

Unread post by asif e elahi » Thu Jul 28, 2016 9:56 pm

jagdish wrote:Total number of whole number integer ordered pair $(n,r)$ in $\displaystyle \binom{n}{r} = 120$
You can use the well known fact that $\frac{n}{gcd(n,k)} \mid \binom{n}{k} \text{ } \forall n,k\in \mathbb{N}$ with $k\leq n$.

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