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A180830
Number of distinct solutions of sum{i=1..7}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 2..n-2
1
0, 0, 0, 0, 4, 98, 1634, 13191, 98721, 509796, 2452572, 9324188, 33559304, 102516038, 302010701, 786309831, 1997861579, 4607230060, 10461759080, 21941200490, 45604744028, 88621893721, 171539771106, 313255557883, 571763758062
OFFSET
1,5
COMMENTS
Column 7 of A180834
LINKS
EXAMPLE
Solutions for sum of products of 7 2..3 pairs = 1 (mod 5) are
(2*2 + 2*2 + 2*2 + 2*3 + 2*3 + 2*3 + 2*3)
(2*2 + 2*2 + 2*3 + 2*3 + 2*3 + 2*3 + 3*3)
(2*2 + 2*3 + 2*3 + 2*3 + 2*3 + 3*3 + 3*3)
(2*3 + 2*3 + 2*3 + 2*3 + 3*3 + 3*3 + 3*3)
CROSSREFS
Sequence in context: A024384 A368004 A320358 * A361883 A265721 A224475
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 20 2010
STATUS
approved