Results 11 to 20 of about 97,613 (280)
On a divisor of the central binomial coefficient [PDF]
The Ramanujan Journal, 2021 It is well known that for all $n\geq1$ the number $n+ 1$ is a divisor of the central binomial coefficient ${2n\choose n}$. Since the $n$th central binomial coefficient equals the number of lattice paths from $(0,0)$ to $(n,n)$ by unit steps north or east, a natural question is whether there is a way to partition these paths into sets of $n+ 1$ paths or
Matthew Just, Maxwell Schneider
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Some combinatorial identities containing central binomial coefficients or Catalan numbers* [PDF]
Applied Mathematics in Science and Engineering, 2023 In the article, by virtue of Maclaurin's expansions of the arcsine function and its square and cubic, the authors give a short proof of a sum formula of a Maclaurin's series with coefficients containing reciprocals of the Catalan numbers; establish four ...
Feng Qi, Da-Wei Niu, Dongkyu Lim
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Products and Sums Divisible by Central Binomial Coefficients [PDF]
The Electronic Journal of Combinatorics, 2013 In this paper we study products and sums divisible by central binomial coefficients. We show that $$2(2n+1)\binom{2n}n\ \bigg|\ \binom{6n}{3n}\binom{3n}n\ \ \mbox{for all}\ n=1,2,3,\ldots.$$ Also, for any nonnegative integers $k$ and $n$ we have $$\binom {2k}k\ \bigg|\ \binom{4n+2k+2}{2n+k+1}\binom{2n+k+1}{2k}\binom{2n-k+1}n$$ and $$\binom{2k}k\ \bigg|\
Zhi‐Wei Sun
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Fifteen series on harmonic numbers and quintic central binomial coefficients [PDF]
Discrete Mathematics LettersChunli Li, Wenchang Chu
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Sums of Reciprocals of the Central Binomial Coefficients [PDF]
, 2006 We consider a set of combinatorial sums involving the reciprocals of the central binomial coefficients and try to solve (or close) them by means of generating functions. We obtain a number of results for infinite sums, in some of which the golden ratio ! appears.
Renzo Sprugnoli
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On congruences related to central binomial coefficients
Journal of Number Theory, 2011 It is known that $\sum_{k=0}^\infty\binom{2k}{k}/((2k+1)4^k)= /2$ and $\sum_{k=0}^\infty\binom{2k}{k}/((2k+1)16^k)= /3$. In this paper we obtain their p-adic analogues such as $$\sum_{p/23 is a prime and E_0,E_1,E_2,... are Euler numbers. Besides these, we also deduce some other congruences related to central binomial coefficients.
Zhi‐Wei Sun
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Central binomial coefficients divisible by or coprime to their indices [PDF]
International Journal of Number Theory, 2017 Let [Formula: see text] be the set of all positive integers [Formula: see text] such that [Formula: see text] divides the central binomial coefficient [Formula: see text]. Pomerance proved that the upper density of [Formula: see text] is at most [Formula: see text]. We improve this bound to [Formula: see text].
Carlo Sanna
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Practical central binomial coefficients [PDF]
Quaestiones Mathematicae, 2020 A practical number is a positive integer $n$ such that all positive integers less than $n$ can be written as a sum of distinct divisors of $n$. Leonetti and Sanna proved that, as $x \to +\infty$, the central binomial coefficient $\binom{2n}{n}$ is a practical number for all positive integers $n \leq x$ but at most $O(x^{0.88097})$ exceptions.
Carlo Sanna
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Applications of Lehmer’s Infinite Series Involving Reciprocals of the Central Binomial Coefficients [PDF]
Journal of Function Spaces, 2022 The main objective of this paper is to establish several new closed-form evaluations of the generalized hypergeometric function F
B. R. Srivatsa Kumar +2 more
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Factors of certain sums involving central q-binomial coefficients [PDF]
Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas, 2021 Recently, Ni and Pan proved a $q$-congruence on certain sums involving central $q$-binomial coefficients, which was conjectured by Guo. In this paper, we give a generalization of this $q$-congruence and confirm another $q$-congruence, also conjectured by Guo.
Victor J. W. Guo, Su-Dan Wang
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