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A010390 Squares mod 28. 1
0, 1, 4, 8, 9, 16, 21, 25 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..8.

MATHEMATICA

Union[PowerMod[Range[28], 2, 28]] (* Alonso del Arte, Nov 28 2019 *)

PROG

(Sage) [quadratic_residues(28)] # Zerinvary Lajos, May 24 2009

(Scala) (1 to 28).map(n => n * n).map(_ % 28).toSet.toSeq.sorted // Alonso del Arte, Nov 28 2019

CROSSREFS

Cf. A028741.

Sequence in context: A134344 A324278 A119315 * A003624 A280387 A243180

Adjacent sequences:  A010387 A010388 A010389 * A010391 A010392 A010393

KEYWORD

nonn,fini,full

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified March 2 06:30 EST 2021. Contains 341743 sequences. (Running on oeis4.)