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A180797 Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 0 (mod n), with x() in 0..n-1.

%I A180797 #6 Jun 02 2025 03:06:21
%S A180797 1,12,87,549,2338,9383,28783,85956,213618,518268,1100399,2370275,
%T A180797 4457359,8595967,15130785,26913348,43848123,74308434,114423976,
%U A180797 184270107,274414305,419987334,601573248,905711494,1247825148,1806542438
%N A180797 Number of distinct solutions of sum{i=1..5}(x(2i-1)*x(2i)) = 0 (mod n), with x() in 0..n-1.
%C A180797 Column 5 of A180803
%H A180797 R. H. Hardin, <a href="/A180797/b180797.txt">Table of n, a(n) for n=1..249</a>
%e A180797 Solutions for sum of products of 5 0..1 pairs = 0 (mod 2) are
%e A180797 (0*0 + 0*0 + 0*0 + 0*0 + 0*0) (0*0 + 0*0 + 0*0 + 0*0 + 0*1)
%e A180797 (0*0 + 0*0 + 0*0 + 0*1 + 0*1) (0*0 + 0*0 + 0*0 + 1*1 + 1*1)
%e A180797 (0*0 + 0*0 + 0*1 + 0*1 + 0*1) (0*0 + 0*0 + 0*1 + 1*1 + 1*1)
%e A180797 (0*0 + 0*1 + 0*1 + 0*1 + 0*1) (0*0 + 0*1 + 0*1 + 1*1 + 1*1)
%e A180797 (0*0 + 1*1 + 1*1 + 1*1 + 1*1) (0*1 + 0*1 + 0*1 + 0*1 + 0*1)
%e A180797 (0*1 + 0*1 + 0*1 + 1*1 + 1*1) (0*1 + 1*1 + 1*1 + 1*1 + 1*1)
%K A180797 nonn
%O A180797 1,2
%A A180797 _R. H. Hardin_, suggested by _Max Alekseyev_ in the Sequence Fans Mailing List, Sep 20 2010