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%I #20 Sep 08 2022 08:44:37
%S 0,1,4,6,7,9,13,16,22,24,25,28,30,33,34,36,42,45,49,51,52,54,57,58,63,
%T 64,67,78,81,82
%N Squares mod 87.
%t Union[PowerMod[Range[87], 2, 87]] (* _Alonso del Arte_, Dec 29 2019 *)
%o (Sage) [quadratic_residues(87)] # _Zerinvary Lajos_, May 28 2009
%o (Scala) (1 to 87).map(n => n * n % 87).toSet.toSeq.sorted // _Alonso del Arte_, Dec 29 2019
%o (Magma) [n: n in [0..86] | IsSquare(R! n) where R:= ResidueClassRing(87)]; // _Vincenzo Librandi_, Dec 30 2019
%Y Cf. A028800.
%K nonn,fini,full,easy
%O 1,3
%A _N. J. A. Sloane_