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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 5 of A180813

LINKS

R. H. Hardin, Table of n, a(n) for n=1..250

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

Adjacent sequences:  A180804 A180805 A180806 * A180808 A180809 A180810

KEYWORD

nonn

AUTHOR

R. H. Hardin, suggested by Max Alekseyev in the Sequence Fans Mailing List, Sep 20 2010

STATUS

approved

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Last modified July 31 02:33 EDT 2021. Contains 346367 sequences. (Running on oeis4.)