%I #17 Aug 31 2024 04:26:37

%S 1,2,3,4,5,6,7,8,9,10,11,13,14,15,16,17,18,19,20,21,22,23,25,26,27,28,

%T 29,30,31,32,33,34,35,36,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,

%U 53,54,55,56,57,58,59,61,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77

%N Numbers k such that gcd(2k+1, numerator(Bernoulli(4k+2))) is squarefree.

%H Amiram Eldar, <a href="/A098240/b098240.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[80],SquareFreeQ[GCD[2#+1,BernoulliB[4#+2]]]&] (* _Harvey P. Dale_, Jul 23 2013 *)

%o (PARI) for(n=1, 3000, if(issquarefree(gcd(2*n+1, numerator(bernfrac(4*n+2)))), print1(n", "))) \\ Herman Jamke (hermanjamke(AT)fastmail.fm), Nov 02 2006

%Y Complement of A098242.

%Y Cf. A005117, A027641, A027642.

%K nonn

%O 1,2

%A _Ralf Stephan_, Sep 01 2004