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A166715 Irregular triangle read by rows: row n lists nonzero quadratic residues modulo the n-th term of A123239. 2
1, 1, 1, 3, 4, 5, 9, 1, 3, 4, 9, 10, 12, 1, 3, 4, 7, 9, 10, 11, 12, 16, 21, 25, 26, 27, 28, 30, 33, 34, 36, 1, 2, 4, 5, 8, 9, 10, 16, 18, 20, 21, 23, 25, 31, 32, 33, 36, 37, 39, 40, 1, 3, 4, 5, 7, 9, 12, 15, 16, 17, 19, 20, 21, 22, 25, 26, 27 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Quadratic Residue.

EXAMPLE

Triangle starts:

1;

1;

1,3,4,5,9;

1,3,4,9,10,12;

...

Modulo A123239(3)=11, the quadratic residues are 1,3,4,5,9.

MATHEMATICA

MangammalQ[p_]:=Block[{k=3}, While[k>2, k=Mod[3k, p]]; k!=2];

A123239=Select[Prime[Range[17]], MangammalQ];

A166715=Flatten[Union[Mod[Range[Floor[#/2]]^2, #]]&/@A123239] (* Ray Chandler, Jul 21 2011 *)

CROSSREFS

Cf. A046071, A063987, A123239.

Sequence in context: A010375 A095028 A011246 * A330577 A020863 A215496

Adjacent sequences:  A166712 A166713 A166714 * A166716 A166717 A166718

KEYWORD

nonn,tabf

AUTHOR

A.K. Devaraj, Oct 20 2009

EXTENSIONS

Edited by N. J. A. Sloane, Oct 22 2009

Edited by Charles R Greathouse IV, Oct 28 2009

Edited, corrected and extended by Ray Chandler, Jul 21 2011

STATUS

approved

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Last modified May 31 20:23 EDT 2020. Contains 334748 sequences. (Running on oeis4.)