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A180776 Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 1..n-1.

%I A180776 #5 Jun 02 2025 03:04:37
%S A180776 0,0,7,62,402,1960,7587,25470,73146,193036,455161,1022770,2098782,
%T A180776 4196208,7797217,14286908,24527232,42125055,67955391,110571248,
%U A180776 170260213,264585538,390623343,588725404,837466268,1220597598,1696535256
%N A180776 Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 0 (mod n), with x() only in 1..n-1.
%C A180776 Column 5 of A180782
%H A180776 R. H. Hardin, <a href="/A180776/b180776.txt">Table of n, a(n) for n=1..249</a>
%e A180776 Solutions for sum of products of 5 1..2 pairs = 0 (mod 3) are
%e A180776 (1*1 + 1*1 + 1*1 + 1*1 + 1*2) (1*1 + 1*1 + 1*1 + 1*2 + 2*2)
%e A180776 (1*1 + 1*1 + 1*2 + 2*2 + 2*2) (1*1 + 1*2 + 1*2 + 1*2 + 1*2)
%e A180776 (1*1 + 1*2 + 2*2 + 2*2 + 2*2) (1*2 + 1*2 + 1*2 + 1*2 + 2*2)
%e A180776 (1*2 + 2*2 + 2*2 + 2*2 + 2*2)
%K A180776 nonn
%O A180776 1,3
%A A180776 _R. H. Hardin_ Sep 20 2010