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A180821 Number of distinct solutions of sum{i=1..9}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 2..n-2 1
0, 0, 0, 1, 11, 409, 6946, 108997, 1113650, 9684748, 64448228, 375427744, 1820591506, 7980182839, 30660616489, 109065451832, 351179673979, 1065973101574, 2992063116800, 8019394451018, 20182278132284, 48949438473158 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,5
COMMENTS
Column 9 of A180823
LINKS
EXAMPLE
Solutions for sum of products of 9 2..3 pairs = 0 (mod 5) are
(2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*3 + 2*3)
(2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*3 + 2*3 + 3*3)
(2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*3 + 2*3 + 3*3 + 3*3)
(2*2 + 2*2 + 2*2 + 2*2 + 2*3 + 2*3 + 3*3 + 3*3 + 3*3)
(2*2 + 2*2 + 2*2 + 2*3 + 2*3 + 3*3 + 3*3 + 3*3 + 3*3)
(2*2 + 2*2 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3)
(2*2 + 2*2 + 2*3 + 2*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3)
(2*2 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 3*3)
(2*2 + 2*3 + 2*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3)
(2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 3*3 + 3*3)
(2*3 + 2*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3)
CROSSREFS
Sequence in context: A067406 A046281 A180833 * A361889 A364369 A285926
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 20 2010
STATUS
approved

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Last modified March 28 16:34 EDT 2024. Contains 371254 sequences. (Running on oeis4.)