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%I #22 Dec 22 2019 16:19:53
%S 0,1,4,9,12,16,20,25,33,36,44,48,49,56,60,64,80,81
%N Squares mod 88.
%e 48 is in the sequence since x^2 = 48 mod 88 has the solutions x = 20, 24, 64, 68.
%e 49 = 7^2 and is thus obviously in the sequence.
%e There are no solutions to x^2 = 50 mod 88, so 50 is not in the sequence.
%t Union[PowerMod[Range[88], 2, 88]] (* _Alonso del Arte_, Apr 05 2017 *)
%o (Sage) [quadratic_residues(88)] # _Zerinvary Lajos_, May 28 2009
%o (Scala) (1 to 88).map(n => (n * n) % 88).toSet.toSeq.sorted // _Alonso del Arte_, Dec 22 2019
%Y Cf. A028801.
%K nonn,fini,full,easy
%O 1,3
%A _N. J. A. Sloane_