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Squares mod 19.
1

%I #24 Nov 13 2023 07:44:31

%S 0,1,4,5,6,7,9,11,16,17

%N Squares mod 19.

%t Union[PowerMod[Range[19], 2, 19]] (* _Alonso del Arte_, Dec 19 2019 *)

%o (Sage) [quadratic_residues(19)] # _Zerinvary Lajos_, May 24 2009

%o (Scala) (1 to 19).map(n => (n * n) % 19).toSet.toSeq.sorted // _Alonso del Arte_, Dec 19 2019

%Y Row 19 of A096008.

%Y Cf. A028732.

%K nonn,fini,full

%O 1,3

%A _N. J. A. Sloane_