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arXiv · 1906.07652

On the divisibility of binomial coefficients

Sílvia Casacuberta
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Abstract

In Pacific J. Math. 292 (2018), 223-238, Shareshian and Woodroofe asked if for every positive integer $n$ there exist primes $p$ and $q$ such that, for all integers $k$ with $1 \leq k \leq n-1$, the binomial coefficient $\binom{n}{k}$ is divisible by at least one of $p$ or $q$. We give conditions under which a number $n$ has this property and discuss a variant of this problem involving more than two primes. We prove that every positive integer $n$ has infinitely many multiples with this property.

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Sílvia Casacuberta. 2019-06-16. On the divisibility of binomial coefficients. https://arxiv.org/abs/1906.07652

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