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%I #21 May 24 2020 03:37:43
%S 0,1,3,5,7,9,11,13,17,19,23,25,27,29,31,37,39,41,43,47,49,53,55,59,61,
%T 67,71,73,79,81,83,89,93,97,101,103,107,109,111,113,119,121,125,127,
%U 131,137,139,149,151,155,157,161,163,167,169,173,179,181,185,191,193,197
%N Numbers k such that k and binomial(2*k, k) are relatively prime.
%H Chai Wah Wu, <a href="/A082916/b082916.txt">Table of n, a(n) for n = 1..10000</a>
%F It seems that a(n) is asymptotic to c*n*log(n) with 0.7<c<0.8.
%t Select[Range[0, 100], CoprimeQ[Binomial[2*#, #], #] &] (* _Amiram Eldar_, May 24 2020 *)
%o (PARI) isok(n) = gcd(n, binomial(2*n, n)) == 1; \\ _Michel Marcus_, Dec 04 2013
%o (Python)
%o from __future__ import division
%o from fractions import gcd
%o A082916_list, b = [], 1
%o for n in range(10**5):
%o if gcd(n,b) == 1:
%o A082916_list.append(n)
%o b = b*(4*n+2)//(n+1) # _Chai Wah Wu_, Mar 25 2016
%Y Cf. A000984 (central binomial coefficients).
%K nonn
%O 1,3
%A _Benoit Cloitre_, May 25 2003
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