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A180785 Number of distinct solutions of sum{i=1..3}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 1..n-1.

%I A180785 #5 Jun 02 2025 03:05:22
%S A180785 0,1,3,14,46,106,254,494,939,1528,2668,3958,6334,8641,13239,17240,
%T A180785 25227,31128,44660,53786,74111,86712,118779,134632,181755,202431,
%U A180785 266175,296323,387533,412008,544121,582432,736568,786710,1006750,1037604,1336781
%N A180785 Number of distinct solutions of sum{i=1..3}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 1..n-1.
%C A180785 Column 3 of A180793
%H A180785 R. H. Hardin, <a href="/A180785/b180785.txt">Table of n, a(n) for n=1..444</a>
%e A180785 Solutions for sum of products of 3 1..3 pairs = 1 (mod 4) are
%e A180785 (1*1 + 1*1 + 1*3) (1*1 + 1*2 + 1*2) (1*1 + 1*2 + 2*3) (1*1 + 1*3 + 3*3)
%e A180785 (1*1 + 2*2 + 2*2) (1*1 + 2*3 + 2*3) (1*2 + 1*2 + 3*3) (1*2 + 1*3 + 2*2)
%e A180785 (1*2 + 2*3 + 3*3) (1*3 + 1*3 + 1*3) (1*3 + 2*2 + 2*3) (1*3 + 3*3 + 3*3)
%e A180785 (2*2 + 2*2 + 3*3) (2*3 + 2*3 + 3*3)
%K A180785 nonn
%O A180785 1,3
%A A180785 _R. H. Hardin_ Sep 20 2010