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A180813 T(n,k)=number of distinct solutions of sum{i=1..k}(x(2i-1)*x(2i)) = 1 (mod n), with x() in 0..n-1 10
0, 0, 1, 0, 2, 2, 0, 4, 7, 2, 0, 6, 18, 12, 3, 0, 9, 42, 50, 24, 2, 0, 12, 84, 166, 136, 31, 4, 0, 16, 153, 474, 612, 262, 59, 4, 0, 20, 264, 1200, 2325, 1649, 583, 74, 4, 0, 25, 429, 2768, 7752, 8468, 4501, 974, 111, 3, 0, 30, 666, 5920, 23256, 37264, 28778, 9772, 1794, 121 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.0...0....0.....0......0.......0........0.........0..........0...........0

.1...2....4.....6......9......12.......16........20.........25..........30

.2...7...18....42.....84.....153......264.......429........666........1001

.2..12...50...166....474....1200.....2768......5920......11900.......22696

.3..24..136...612...2325....7752....23256.....63954.....163438......392250

.2..31..262..1649...8468...37264...145098....510927....1652886.....4972016

.4..59..583..4501..28778..158239...768537...3362288...13449080....49761505

.4..74..974..9772..79670..550860..3329262..17975676...88130750...397307654

.4.111.1794.21631.212049.1766580.12867751..83628636..492442470..2659084116

.3.121.2603.39911.484180.4912624.43149935.335900991.2357340087.15109820870

LINKS

R. H. Hardin, Table of n, a(n) for n=1..2016

CROSSREFS

Sequence in context: A072690 A199454 A244130 * A194656 A108520 A099087

Adjacent sequences:  A180810 A180811 A180812 * A180814 A180815 A180816

KEYWORD

nonn,tabl

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 November 24 07:01 EST 2014. Contains 249870 sequences.