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Outline

Digit sums of binomial sums

2012, Journal of Number Theory

https://doi.org/10.1016/J.JNT.2011.07.004

Abstract

Let b 2 be a fixed positive integer and let S(n) be a certain type of binomial sum. In this paper, we show that for most n the sum of the digits of S(n) in base b is at least c 0 log n/(log log n), where c 0 is some positive constant depending on b and on the sequence of binomial sums. Our results include middle binomial coefficients 2n n and Apéry numbers A n. The proof uses a result of McIntosh regarding the asymptotic expansions of such binomial sums as well as Baker's theorem on lower bounds for nonzero linear forms in logarithms of algebraic numbers.

References (8)

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