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A010449 Squares mod 88. 1
0, 1, 4, 9, 12, 16, 20, 25, 33, 36, 44, 48, 49, 56, 60, 64, 80, 81 (list; graph; refs; listen; history; text; internal format)
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: A337103 A312855 A312856 * A210607 A312857 A309134

Adjacent sequences:  A010446 A010447 A010448 * A010450 A010451 A010452

KEYWORD

nonn,fini,full,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified December 2 07:40 EST 2020. Contains 338868 sequences. (Running on oeis4.)