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A180804 Number of distinct solutions of sum{i=1..2}(x(2i-1)*x(2i)) = 1 (mod n), with x() in 0..n-1 1
0, 2, 7, 12, 24, 31, 59, 74, 111, 121, 202, 208, 323, 310, 454, 484, 695, 597, 957, 874, 1183, 1125, 1665, 1448, 2070, 1823, 2439, 2304, 3273, 2524, 3980, 3464, 4367, 3982, 5470, 4440, 6692, 5515, 7110, 6488, 9056, 6728, 10422, 8592, 10542, 9666, 13554 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 2 of A180813

LINKS

R. H. Hardin, Table of n, a(n) for n=1..999

EXAMPLE

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

(0*0 + 1*1) (0*0 + 2*2) (0*1 + 1*1) (0*1 + 2*2) (0*2 + 1*1) (0*2 + 2*2)

(1*2 + 1*2)

CROSSREFS

Sequence in context: A293330 A135541 A288656 * A122264 A079824 A059329

Adjacent sequences:  A180801 A180802 A180803 * A180805 A180806 A180807

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 April 6 08:44 EDT 2020. Contains 333268 sequences. (Running on oeis4.)