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A180810 Number of distinct solutions of sum{i=1..8}(x(2i-1)*x(2i)) = 1 (mod n), with x() in 0..n-1 1
0, 20, 429, 5920, 63954, 510927, 3362288, 17975676, 83628636, 335900991, 1222011613, 3989760008, 12105111844, 33802351881, 89361617169, 221117356432, 524533042878, 1178959072101, 2564070846089, 5330170938874, 10795501502457 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 8 of A180813

LINKS

R. H. Hardin, Table of n, a(n) for n=1..183

EXAMPLE

Solutions for sum of products of 8 0..1 pairs = 1 (mod 2) are

(0*0 + 0*0 + 0*0 + 0*0 + 0*0 + 0*0 + 0*0 + 1*1)

(0*0 + 0*0 + 0*0 + 0*0 + 0*0 + 0*0 + 0*1 + 1*1)

(0*0 + 0*0 + 0*0 + 0*0 + 0*0 + 0*1 + 0*1 + 1*1)

(0*0 + 0*0 + 0*0 + 0*0 + 0*1 + 0*1 + 0*1 + 1*1)

(0*0 + 0*0 + 0*0 + 0*0 + 0*0 + 1*1 + 1*1 + 1*1)

(0*0 + 0*0 + 0*0 + 0*0 + 0*1 + 1*1 + 1*1 + 1*1)

(0*0 + 0*0 + 0*0 + 0*1 + 0*1 + 0*1 + 0*1 + 1*1)

(0*0 + 0*0 + 0*0 + 0*1 + 0*1 + 1*1 + 1*1 + 1*1)

(0*0 + 0*0 + 0*0 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1)

(0*0 + 0*0 + 0*1 + 0*1 + 0*1 + 0*1 + 0*1 + 1*1)

(0*0 + 0*0 + 0*1 + 0*1 + 0*1 + 1*1 + 1*1 + 1*1)

(0*0 + 0*0 + 0*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1)

(0*0 + 0*1 + 0*1 + 0*1 + 0*1 + 0*1 + 0*1 + 1*1)

(0*0 + 0*1 + 0*1 + 0*1 + 0*1 + 1*1 + 1*1 + 1*1)

(0*0 + 0*1 + 0*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1)

(0*0 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1)

(0*1 + 0*1 + 0*1 + 0*1 + 0*1 + 0*1 + 0*1 + 1*1)

(0*1 + 0*1 + 0*1 + 0*1 + 0*1 + 1*1 + 1*1 + 1*1)

(0*1 + 0*1 + 0*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1)

(0*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1)

CROSSREFS

Sequence in context: A268738 A215290 A130832 * A109116 A190922 A136257

Adjacent sequences:  A180807 A180808 A180809 * A180811 A180812 A180813

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 12 19:35 EDT 2020. Contains 335668 sequences. (Running on oeis4.)