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A180832 Number of distinct solutions of sum{i=1..9}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 2..n-2 1
0, 0, 0, 0, 15, 263, 6946, 95702, 1113010, 9143911, 64448228, 363369141, 1820591529, 7808981077, 30658462967, 107320405217, 351179673988, 1052229547028, 2992063116924, 7932504265966, 20180975666040, 48485253590942 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Column 9 of A180834

LINKS

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

EXAMPLE

Solutions for sum of products of 9 2..3 pairs = 1 (mod 5) are

(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*2 + 2*2 + 3*3)

(2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 3*3 + 3*3)

(2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 3*3 + 3*3 + 3*3)

(2*2 + 2*2 + 2*2 + 2*2 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3)

(2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 3*3 + 3*3 + 3*3 + 3*3)

(2*2 + 2*2 + 2*2 + 2*2 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3)

(2*2 + 2*2 + 2*2 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 3*3)

(2*2 + 2*2 + 2*2 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3)

(2*2 + 2*2 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 3*3 + 3*3)

(2*2 + 2*2 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3)

(2*2 + 2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 3*3 + 3*3 + 3*3)

(2*2 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3)

(2*3 + 2*3 + 2*3 + 2*3 + 2*3 + 3*3 + 3*3 + 3*3 + 3*3)

(3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3 + 3*3)

CROSSREFS

Sequence in context: A099273 A206230 A209263 * A013381 A013384 A013380

Adjacent sequences:  A180829 A180830 A180831 * A180833 A180834 A180835

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 20 2010

STATUS

approved

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Last modified July 2 18:27 EDT 2022. Contains 355029 sequences. (Running on oeis4.)