cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A283074 Numbers k such that the central binomial coefficient C(2*k,k) is divisible by k^5.

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%I A283074 #29 Jan 10 2022 05:26:37
%S A283074 1,84331608790,94482127740,164273806200,438726722148,541278246600,
%T A283074 549361342530,808172086449,912226745430,959218287720,1017676553985,
%U A283074 1017868271175,1078659050256,1286556180525,1418394308100,1475851476960,1489765799610,1535790227400,1562434592400,1642639268270
%N A283074 Numbers k such that the central binomial coefficient C(2*k,k) is divisible by k^5.
%C A283074 Equivalently, numbers k such that the k-th Catalan number C(2*k,k)/(k+1) is divisible by k^5.
%C A283074 The asymptotic density of this sequence is 2.83248121476... * 10^(-10) (Ford and Konyagin, 2021). - _Amiram Eldar_, Jan 26 2021
%H A283074 Giovanni Resta, <a href="/A283074/b283074.txt">Table of n, a(n) for n = 1..123</a> (terms < 10^13).
%H A283074 Kevin Ford and Sergei Konyagin, <a href="https://doi.org/10.1090/tran/8183">Divisibility of the central binomial coefficient binomial(2n, n)</a>, Trans. Amer. Math. Soc., Vol. 374, No. 2 (2021), pp. 923-953; <a href="https://arxiv.org/abs/1909.03903">arXiv preprint</a>, arXiv:1909.03903 [math.NT], 2019-2020.
%e A283074 The central binomial coefficient C(2*84331608790,84331608790) is divisible by 84331608790^5.
%Y A283074 Cf. A000108, A000984, A014847, A121943, A282163, A282346, A283073, A282672.
%K A283074 nonn
%O A283074 1,2
%A A283074 _Lucian Craciun_, Feb 28 2017
%E A283074 a(3)-a(20) from _Giovanni Resta_, Mar 03 2017