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%I #15 May 01 2020 23:04:55
%S 3,6,7,11,12,13,14,15,17,19,22,24,26,27,28,29,30,34,35,38
%N Nonsquares mod 41.
%e x^2 = 7 mod 41 has no solutions, so 7 is in the sequence.
%e x^2 = 8 mod 41 has the solutions x = 7 and x = 34. Hence 8 is not in the sequence.
%t Complement[Range[40], PowerMod[Range[41], 2, 41]] (* _Alonso del Arte_, Jan 12 2017 *)
%o (Scala) (0 to 40).diff((1 to 41).map(n => n * n % 41)) // _Alonso del Arte_, May 01 2020
%Y Cf. A010402, A028795.
%K nonn,fini,full,easy
%O 1,1
%A _N. J. A. Sloane_