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A180780 Number of distinct solutions of sum{i=1..9}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 1..n-1 1
0, 0, 22, 499, 9730, 136491, 1430727, 11783122, 78770456, 443607864, 2151608155, 9218591346, 35373572400, 123749340262, 398005623516, 1192411118090, 3344070542568, 8869510553867, 22304900540593, 53635016669434 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Column 9 of A180782

LINKS

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

EXAMPLE

Solutions for sum of products of 9 1..2 pairs = 0 (mod 3) are

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

(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 2*2)

(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 2*2 + 2*2)

(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2)

(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 2*2 + 2*2 + 2*2)

(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 2*2)

(1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2)

(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 2*2 + 2*2 + 2*2 + 2*2)

(1*1 + 1*1 + 1*1 + 1*1 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)

(1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2)

(1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2)

(1*1 + 1*1 + 1*1 + 2*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 + 2*2)

(1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2)

(1*1 + 1*1 + 2*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 + 2*2 + 2*2)

(1*1 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)

(1*1 + 2*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 + 1*2 + 1*2)

(1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2)

(1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)

(2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)

CROSSREFS

Sequence in context: A041221 A041926 A230350 * A121904 A158629 A253777

Adjacent sequences:  A180777 A180778 A180779 * A180781 A180782 A180783

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 20 2010

STATUS

approved

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Last modified July 1 12:30 EDT 2022. Contains 354973 sequences. (Running on oeis4.)