A180796 Number of distinct solutions of sum{i=1..4}(x(2i-1)*x(2i)) = 0 (mod n), with x() in 0..n-1.

1, 9, 45, 205, 620, 1957, 4507, 11171, 22146, 45350, 78661, 151695, 234757, 405587, 621513, 995842, 1396875, 2214555, 2949517, 4476311, 5932188, 8399584, 10743228, 15648807, 19058660, 26160160, 32743869, 43862757, 52161089, 71513890, 82339801

Offset: 1

Author

R. H. Hardin, suggested by Max Alekseyev in the Sequence Fans Mailing List, Sep 20 2010

Keywords

• nonn

Comments

Column 4 of A180803

Examples

			Solutions for sum of products of 4 0..1 pairs = 0 (mod 2) are
(0*0 + 0*0 + 0*0 + 0*0) (0*0 + 0*0 + 0*0 + 0*1) (0*0 + 0*0 + 0*1 + 0*1)
(0*0 + 0*0 + 1*1 + 1*1) (0*0 + 0*1 + 0*1 + 0*1) (0*0 + 0*1 + 1*1 + 1*1)
(0*1 + 0*1 + 0*1 + 0*1) (0*1 + 0*1 + 1*1 + 1*1) (1*1 + 1*1 + 1*1 + 1*1)
		

Links

• R. H. Hardin, Table of n, a(n) for n=1..376