%I #20 Dec 13 2019 14:03:03
%S 0,1,3,4,9,10,12
%N Squares mod 13.
%t Union[PowerMod[Range[13], 2, 13]] (* _Alonso del Arte_, Dec 13 2019 *)
%o (Sage) [quadratic_residues(13)] # _Zerinvary Lajos_, May 24 2009
%o (Scala) (1 to 13).map(n => (n * n) % 13).toSet.toSeq.sorted // _Alonso del Arte_, Dec 13 2019
%Y Row 13 of A096008.
%Y Cf. A028726.
%K nonn,fini,full
%O 1,3
%A _N. J. A. Sloane_