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.

A056060 The powerfree part of the central binomial coefficients.

This page as a plain text file.
%I A056060 #9 Sep 05 2020 07:46:44
%S A056060 1,2,3,6,10,5,35,70,14,7,462,231,429,429,715,1430,24310,12155,92378,
%T A056060 46189,88179,88179,1352078,676039,52003,52003,7429,7429,1077205,
%U A056060 1077205,33393355,66786710,43214930,21607465,181502706,90751353,176726319,176726319,7658140490
%N A056060 The powerfree part of the central binomial coefficients.
%H A056060 Amiram Eldar, <a href="/A056060/b056060.txt">Table of n, a(n) for n = 1..3388</a>
%F A056060 a(n) = A055231(A001405(n)).
%e A056060 n=14, binomial(14,7) = 3432 = 8*3*11*13. The largest square divisor is 4, and the squarefree part is 858. So GCD(4,858) = 2 and a(14) = 858/2 = 429.
%t A056060 a[n_] := Denominator[(b = Binomial[n, Floor[n/2]])/(Times @@ First /@ FactorInteger[b])^2]; Array[a, 36] (* _Amiram Eldar_, Sep 05 2020 *)
%Y A056060 Cf. A001405, A000188, A008833, A007913, A055229, A055231, A046098, A034974, A056056, A056057, A056058, A056059, A056060, A056061.
%K A056060 nonn
%O A056060 1,2
%A A056060 _Labos Elemer_, Jul 26 2000
%E A056060 New name and more terms from _Amiram Eldar_, Sep 05 2020