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A180807
Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 1 (mod n), with x() in 0..n-1
1
0, 9, 84, 474, 2325, 8468, 28778, 79670, 212049, 484180, 1100299, 2210931, 4457004, 8097649, 15007266, 25353330, 43846972, 69637926, 114422914, 173562451, 272208103, 396802048, 601571401, 847452462, 1246173200, 1706973960
OFFSET
1,2
COMMENTS
Column 5 of A180813
LINKS
EXAMPLE
Solutions for sum of products of 5 0..1 pairs = 1 (mod 2) are
(0*0 + 0*0 + 0*0 + 0*0 + 1*1) (0*0 + 0*0 + 0*0 + 0*1 + 1*1)
(0*0 + 0*0 + 0*1 + 0*1 + 1*1) (0*0 + 0*0 + 1*1 + 1*1 + 1*1)
(0*0 + 0*1 + 0*1 + 0*1 + 1*1) (0*0 + 0*1 + 1*1 + 1*1 + 1*1)
(0*1 + 0*1 + 0*1 + 0*1 + 1*1) (0*1 + 0*1 + 1*1 + 1*1 + 1*1)
(1*1 + 1*1 + 1*1 + 1*1 + 1*1)
CROSSREFS
Sequence in context: A155499 A321294 A242596 * A203455 A272582 A037595
KEYWORD
nonn
AUTHOR
R. H. Hardin, suggested by Max Alekseyev in the Sequence Fans Mailing List, Sep 20 2010
STATUS
approved