A028767 Nonsquares mod 54.

2, 3, 5, 6, 8, 11, 12, 14, 15, 17, 18, 20, 21, 23, 24, 26, 29, 30, 32, 33, 35, 38, 39, 41, 42, 44, 45, 47, 48, 50, 51, 53

Offset

1,1

Links

Table of n, a(n) for n=1..32.

Mathematica

Complement[Range[0, 53], PowerMod[Range[54], 2, 54]] (* Alonso del Arte, Dec 27 2019 *)

Prog

(Scala) (0 to 53).diff((1 to 54).map(n => (n * n) % 54)) // Alonso del Arte, Dec 27 2019
(Magma) [ n: n in [0..53] | not IsSquare(R! n) where R:= ResidueClassRing(54)]; // Vincenzo Librandi, Dec 28 2019

Crossrefs

Cf. A010415.

Sequence in context: A028740 A028794 A028966 * A268226 A138529 A266409

Adjacent sequences: A028764 A028765 A028766 * A028768 A028769 A028770

Keyword

nonn,fini,full,easy

Author

N. J. A. Sloane

Status

approved