%I #5 Mar 31 2012 12:36:15
%S 40,2000,31280,204544,911144,3022220,8655424,21284040,47231344,
%T 96369040,187026380,335425808,582302520,973424372,1563214444,
%U 2426917164,3699260196,5472064152,7976593144,11351136420,15868645560,21892595476
%N Number of arrangements of 7 nonzero numbers x(i) in -n..n with the sum of trunc(x(i)/x(i+1)) equal to zero
%C Row 6 of A189545
%H R. H. Hardin, <a href="/A189550/b189550.txt">Table of n, a(n) for n = 1..145</a>
%e Some solutions for n=5
%e .-5....1....1....1...-3....1...-3....2....2...-3...-4...-5...-3...-4...-4....2
%e .-4...-5...-4...-5...-4...-4...-4...-5...-4...-5...-4...-5...-4...-4...-4...-4
%e ..5...-4....4...-2...-3...-4...-5...-2...-2....5....1...-3...-4....2....4....4
%e ..2....3....1....5...-2...-4...-4....3....3....2...-2....2....3....5....5....2
%e .-1...-5....4....3....1....1...-5...-1....3...-1...-1....4...-1...-4....3...-4
%e ..1....5...-1...-1....2....1....4....2...-1....5....5...-3...-3...-3...-2....4
%e .-4....5...-1....3...-3....1....5....2...-4....4....5...-4...-1...-3....3....5
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 23 2011