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A180805 Number of distinct solutions of sum{i=1..3}(x(2i-1)*x(2i)) = 1 (mod n), with x() in 0..n-1 1
0, 4, 18, 50, 136, 262, 583, 974, 1794, 2603, 4560, 6190, 9987, 12617, 19419, 24264, 35818, 41262, 61133, 70126, 97274, 110076, 154038, 167176, 230205, 247554, 328518, 357811, 476360, 485118, 660061, 688320, 874343, 917049, 1189870, 1192404 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A180813

LINKS

R. H. Hardin, Table of n, a(n) for n=1..444

EXAMPLE

Solutions for sum of products of 3 0..2 pairs = 1 (mod 3) are

(0*0 + 0*0 + 1*1) (0*0 + 0*0 + 2*2) (0*0 + 0*1 + 1*1) (0*0 + 0*1 + 2*2)

(0*0 + 0*2 + 1*1) (0*0 + 0*2 + 2*2) (0*0 + 1*2 + 1*2) (0*1 + 0*1 + 1*1)

(0*1 + 0*1 + 2*2) (0*1 + 0*2 + 1*1) (0*1 + 0*2 + 2*2) (0*1 + 1*2 + 1*2)

(0*2 + 0*2 + 1*1) (0*2 + 0*2 + 2*2) (0*2 + 1*2 + 1*2) (1*1 + 1*1 + 1*2)

(1*1 + 1*2 + 2*2) (1*2 + 2*2 + 2*2)

CROSSREFS

Sequence in context: A081528 A056147 A181857 * A120656 A225263 A092349

Adjacent sequences:  A180802 A180803 A180804 * A180806 A180807 A180808

KEYWORD

nonn

AUTHOR

R. H. Hardin, suggested by Max Alekseyev in the Sequence Fans Mailing List, Sep 20 2010

STATUS

approved

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Last modified November 22 20:13 EST 2014. Contains 249827 sequences.