A180779 Number of distinct solutions of sum{i=1..8}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 1..n-1.

0, 1, 15, 327, 4856, 53455, 444003, 2948305, 16112289, 75389116, 307372600, 1122069080, 3701885580, 11258893954, 31699979961, 83910860201, 209004408715, 496246703439, 1121475446118, 2440154664350, 5096346969372, 10323359668079

Offset: 1

Author

R. H. Hardin Sep 20 2010

Keywords

• nonn

Comments

Column 8 of A180782

Examples

			Solutions for sum of products of 8 1..2 pairs = 0 (mod 3) are
(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*1 + 1*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2)
(1*1 + 1*1 + 1*1 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2)
(1*1 + 1*1 + 1*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 + 1*2)
(1*1 + 1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2)
(1*1 + 1*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 + 2*2)
(1*2 + 1*2 + 1*2 + 1*2 + 2*2 + 2*2 + 2*2 + 2*2)
(1*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2 + 2*2)
		

Links

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