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A028740 Nonsquares mod 27. 1
2, 3, 5, 6, 8, 11, 12, 14, 15, 17, 18, 20, 21, 23, 24, 26 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..16.

MATHEMATICA

Complement[Range[0, 26], PowerMod[Range[27], 2, 27]] (* Alonso del Arte, Nov 27 2019 *)

PROG

(Scala) val squaresMod27 = (0 to 26).map(n => n * n).map(_ % 27)

(0 to 26).diff(squaresMod27) // Alonso del Arte, Nov 27 2019

CROSSREFS

Cf. A010389.

Sequence in context: A104424 A028806 A028731 * A028794 A028966 A028767

Adjacent sequences:  A028737 A028738 A028739 * A028741 A028742 A028743

KEYWORD

nonn,fini,full,changed

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified December 7 05:14 EST 2019. Contains 329839 sequences. (Running on oeis4.)