%I #15 Dec 26 2019 05:10:09
%S 2,5,6,7,8,11,14,15,17,18,19,20,21,23,24,26,28,29,31,32,33,34,35,37,
%T 38,41,44,45,46,47,50,53,54,56,57,58,59,60,62,63,65,67,68,70,71,72,73,
%U 74,76,77
%N Nonsquares mod 78.
%t Complement[Range[0, 77], PowerMod[Range[78], 2, 78]] (* _Alonso del Arte_, Dec 26 2019 *)
%o (PARI) for(k=0, 78, if(!issquare(Mod(k, 78)), print1(k, ", "))) \\ _Hugo Pfoertner_, Dec 02 2019
%o (Scala) (0 to 77).diff((1 to 78).map(n => (n * n) % 78)) // _Alonso del Arte_, Dec 26 2019
%Y Cf. A010439.
%K nonn,fini,full,easy
%O 1,1
%A _N. J. A. Sloane_
%E Incorrect term 39 removed by _Alonso del Arte_, Dec 01 2019