A028740 Nonsquares mod 27.

2, 3, 5, 6, 8, 11, 12, 14, 15, 17, 18, 20, 21, 23, 24, 26

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• fini
• full

Crossrefs

Cf. A010389. Subsequence of A028794.

Programs

Mathematica

Complement[Range[0, 26], PowerMod[Range[27], 2, 27]] (* Alonso del Arte, Nov 27 2019 *)

Scala

val squaresMod27 = (0 to 26).map(n => n * n).map(_ % 27)
(0 to 26).diff(squaresMod27) // Alonso del Arte, Nov 27 2019