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A180791
Number of distinct solutions of sum{i=1..9}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 1..n-1
1
0, 1, 18, 502, 9721, 135902, 1430707, 11752870, 78770466, 442714845, 2151608163, 9202214058, 35373572486, 123540794708, 398005342048, 1190430659772, 3344070542314, 8854626554163, 22304900540858, 53543330420874
OFFSET
1,3
COMMENTS
Column 9 of A180793
LINKS
EXAMPLE
Solutions for sum of products of 9 1..2 pairs = 1 (mod 3) are
(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2)
(1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2)
(1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)
(1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2)
(1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)
(1*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)
CROSSREFS
Sequence in context: A282477 A116176 A035023 * A126276 A035277 A011906
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 20 2010
STATUS
approved