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A010389 Squares mod 27. 1
0, 1, 4, 7, 9, 10, 13, 16, 19, 22, 25 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..11.

MATHEMATICA

Union[PowerMod[Range[27], 2, 27]] (* Alonso del Arte, Nov 27 2019 *)

PROG

(Sage) [quadratic_residues(27)] # Zerinvary Lajos, May 24 2009

(Scala) (1 to 27).map(n => n * n).map(_ % 27).toSet.toSeq.sorted // Alonso del Arte, Nov 27 2019

CROSSREFS

Cf. A028740.

Sequence in context: A010380 A056991 A242660 * A010415 A010442 A055047

Adjacent sequences:  A010386 A010387 A010388 * A010390 A010391 A010392

KEYWORD

nonn,fini,full

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified December 14 01:31 EST 2019. Contains 329978 sequences. (Running on oeis4.)