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arXiv · 1710.10884

Divisibility of binomial coefficients by powers of two

Lukas Spiegelhofer·Michael Wallner
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Abstract

For nonnegative integers $j$ and $n$ let $Θ(j,n)$ be the number of entries in the $n$-th row of Pascal's triangle that are not divisible by $2^{j+1}$. In this paper we prove that the family $j\mapstoΘ(j,n)$ usually follows a normal distribution. The method used for proving this theorem involves the computation of first and second moments of $Θ(j,n)$, and uses asymptotic analysis of multivariate generating functions by complex analytic methods, building on earlier work by Drmota (1994) and Drmota, Kauers and Spiegelhofer (2016).

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Lukas Spiegelhofer, Michael Wallner. 2017-10-30. Divisibility of binomial coefficients by powers of two. https://doi.org/10.1016/j.jnt.2018.04.010

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