A010449 Squares mod 88.

0, 1, 4, 9, 12, 16, 20, 25, 33, 36, 44, 48, 49, 56, 60, 64, 80, 81

Offset

1,3

Links

Table of n, a(n) for n=1..18.

Example

48 is in the sequence since x^2 = 48 mod 88 has the solutions x = 20, 24, 64, 68.
49 = 7^2 and is thus obviously in the sequence.
There are no solutions to x^2 = 50 mod 88, so 50 is not in the sequence.

Mathematica

Union[PowerMod[Range[88], 2, 88]] (* Alonso del Arte, Apr 05 2017 *)

Prog

(Sage) [quadratic_residues(88)] # Zerinvary Lajos, May 28 2009
(Scala) (1 to 88).map(n => (n * n) % 88).toSet.toSeq.sorted // Alonso del Arte, Dec 22 2019

Crossrefs

Cf. A028801.

Sequence in context: A348752 A365869 A312856 * A210607 A312857 A309134

Adjacent sequences: A010446 A010447 A010448 * A010450 A010451 A010452

Keyword

nonn,fini,full,easy

Author

N. J. A. Sloane

Status

approved