%I #10 Dec 23 2019 06:07:24
%S 2,5,7,8,10,11,14,15,17,19,20,21,22,23,26,28,29,30,32,33,34,35,37,38,
%T 40,41,42,43,44,45,47,50,51,53,56,57,59,60,61,62,63,65,66,67,68
%N Nonsquares mod 69.
%t Complement[Range[0, 68], PowerMod[Range[69], 2, 69]] (* _Alonso del Arte_, Dec 23 2019 *)
%o (Scala) (0 to 68).diff((1 to 69).map(n => (n * n) % 69)) // _Alonso del Arte_, Dec 23 2019
%Y Cf. A010430.
%K nonn,fini,full,easy
%O 1,1
%A _N. J. A. Sloane_