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A180795
Number of distinct solutions of Sum_{i=1..3}(x(2i-1)*x(2i)) = 0 (mod n), with x() in 0..n-1.
1
1, 6, 21, 68, 142, 355, 589, 1250, 1946, 3372, 4591, 8432, 10054, 16027, 21564, 31228, 35957, 56543, 61282, 92952, 107265, 139286, 154287, 234348, 238495, 313496, 362400, 469556, 476974, 690961, 660676, 896194, 964301, 1162662, 1252820
OFFSET
1,2
LINKS
EXAMPLE
Solutions for sum of products of 3 0..2 pairs = 0 (mod 3) are:
(0*0 + 0*0 + 0*0) (0*0 + 0*0 + 0*1) (0*0 + 0*0 + 0*2) (0*0 + 0*1 + 0*1)
(0*0 + 0*1 + 0*2) (0*0 + 0*2 + 0*2) (0*0 + 1*1 + 1*2) (0*0 + 1*2 + 2*2)
(0*1 + 0*1 + 0*1) (0*1 + 0*1 + 0*2) (0*1 + 0*2 + 0*2) (0*1 + 1*1 + 1*2)
(0*1 + 1*2 + 2*2) (0*2 + 0*2 + 0*2) (0*2 + 1*1 + 1*2) (0*2 + 1*2 + 2*2)
(1*1 + 1*1 + 1*1) (1*1 + 1*1 + 2*2) (1*1 + 2*2 + 2*2) (1*2 + 1*2 + 1*2)
(2*2 + 2*2 + 2*2)
CROSSREFS
Column 3 of A180803.
Sequence in context: A105457 A134931 A119103 * A306089 A107653 A123653
KEYWORD
nonn
AUTHOR
R. H. Hardin, suggested by Max Alekseyev in the Sequence Fans Mailing List, Sep 20 2010
STATUS
approved