A180817 Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 2..n-2

0, 0, 0, 1, 7, 57, 286, 1701, 5969, 22212, 59824, 173319, 385060, 920819, 1831674, 3839358, 6872225, 13243078, 21945628, 39182616, 61892080, 103355368, 155139308, 251041955, 359562489, 554717344, 780642911, 1160794113, 1574984248

Offset

1,5

Comments

Column 5 of A180823

Links

R. H. Hardin, Table of n, a(n) for n=1..251

Example

Solutions for sum of products of 5 2..3 pairs = 0 (mod 5) are
(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 + 3*3 + 3*3) (2*2 + 2*2 + 3*3 + 3*3 + 3*3)
(2*2 + 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)

Crossrefs

Sequence in context: A218428 A365102 A274721 * A201438 A202510 A042187

Adjacent sequences: A180814 A180815 A180816 * A180818 A180819 A180820

Keyword

nonn

Author

R. H. Hardin Sep 20 2010

Status

approved