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%I #5 Mar 31 2012 12:36:16
%S 2,8,15,29,39,61,75,103,124,155,176,225,250,289,325,381,413,475,512,
%T 578,626,688,730,826,877,947,1009,1095,1150,1255,1317,1419,1489,1578,
%U 1650,1789,1862,1959,2040,2176,2254,2391,2476,2601,2708,2831,2918,3098,3197
%N 1/4 the number of arrangements of 3 nonzero numbers x(i) in -n..n with the sum of sign(x(i))*(|x(i)| mod x(i+1)) equal to zero
%C Row 2 of A189951
%H R. H. Hardin, <a href="/A189952/b189952.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions with n=3
%e .-2....3....2....1...-2...-2...-3....1...-3...-3...-3...-3....2....1....3...-3
%e ..2....3....1...-1...-1...-2...-3...-3...-3...-3....3....1...-2....1...-1...-1
%e .-2...-1...-1...-1...-1...-2....1....2....3...-3....3....1....2...-1...-1...-1
%K nonn
%O 1,1
%A _R. H. Hardin_ May 02 2011