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%I #16 Dec 25 2019 23:12:23
%S 0,1,4,6,9,16,19,21,24,25,31,34,36,39,46,49,51,54,61,64,66,69
%N Squares mod 75.
%t Union[PowerMod[Range[75], 2, 75]] (* _Alonso del Arte_, Dec 25 2019 *)
%o (Sage) [quadratic_residues(75)] # _Zerinvary Lajos_, May 28 2009
%o (Scala) (1 to 75).map(n => (n * n) % 75).toSet.toSeq.sorted // _Alonso del Arte_, Dec 25 2019
%Y Cf. A028788.
%K nonn,fini,full,easy
%O 1,3
%A _N. J. A. Sloane_