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%I #11 Jan 13 2020 02:31:42
%S 2,3,5,6,7,8,10,11,12,13,15,17,18,19,20,21,24,26,27,28,31,32,33,34,37,
%T 38,40,41,44,45,46,47,48,50,52,54,55,57,58,59,60,61,62,63,66,67,68,69,
%U 70,71,72,73,75,76,80,82,83,84,85,86,87,89,90
%N Nonsquares mod 91.
%t Complement[Range[0, 90], PowerMod[Range[91], 2, 91]] (* _Alonso del Arte_, Jan 07 2020 *)
%o (Scala) (0 to 90).diff((1 to 91).map(n => n * n % 91)) // _Alonso del Arte_, Jan 13 2020
%Y Cf. A010452.
%K nonn,fini,full,easy
%O 1,1
%A _N. J. A. Sloane_