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A180818
Number of distinct solutions of Sum_{i=1..6}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 2..n-2.
1
0, 0, 0, 1, 4, 102, 715, 5509, 25718, 118806, 408760, 1398428, 3851116, 10645021, 25222196, 59980990, 125991239, 269061589, 515720413, 1009271512, 1807435081, 3294073002, 5559159180, 9631372495, 15454550858, 25498951485, 39499016193
OFFSET
1,5
COMMENTS
Column 6 of A180823.
LINKS
EXAMPLE
Solutions for sum of products of 6 2..3 pairs = 0 (mod 5) are
(2*2 + 2*2 + 2*2 + 2*3 + 2*3 + 2*3) (2*2 + 2*2 + 2*3 + 2*3 + 2*3 + 3*3)
(2*2 + 2*3 + 2*3 + 2*3 + 3*3 + 3*3) (2*3 + 2*3 + 2*3 + 3*3 + 3*3 + 3*3)
CROSSREFS
Cf. A180823.
Sequence in context: A129435 A129702 A220776 * A211047 A326087 A091330
KEYWORD
nonn
AUTHOR
R. H. Hardin, Sep 20 2010
STATUS
approved