%I #9 Aug 06 2019 20:19:28
%S 1,3,4,5,7,8,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,
%T 47,48,49,51,53,55,57,59,60,61,63,65,67,69,71,73,75,77,79,80,81,83,84,
%U 85,87,89,91,93,95,97,99,101,103,104,105
%N Numbers k such that gcd(k!!+1,k-1) > 1.
%C Positions of 1 in A214054; complement of A214586.
%H Clark Kimberling, <a href="/A214585/b214585.txt">Table of n, a(n) for n = 1..1000</a>
%t b[n_]:=n!!;c[n_]:=n;
%t t=Table[m=1;While[GCD[b[n]+m,c[n]-m]==1,m++];m,{n,1,200}] (* A214054 *)
%t Flatten[Position[t,1]] (* A214585 *)
%t Flatten[Position[t,2]] (* A214586 *)
%t Select[Range[120],GCD[#!!+1,#-1]>1&] (* _Harvey P. Dale_, Aug 06 2019 *)
%Y Cf. A214054, A214586.
%K nonn
%O 1,2
%A _Clark Kimberling_, Jul 21 2012