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%I #5 Mar 31 2012 12:36:19
%S 40,1896,28656,191456,834717,2783714,7737762,18951546,41786130,
%T 84902980,162378720,292892946,503182507,835582280,1339061119,
%U 2077237619,3144963614,4653920446,6746522401,9597835033,13398597773,18439060711
%N Number of arrangements of 7 nonzero numbers x(i) in -n..n with the sum of div(x(i),x(i+1)), where div(a,b)=a/b produces the integer quotient implying a nonnegative remainder, equal to zero
%C Row 6 of A190071
%H R. H. Hardin, <a href="/A190076/b190076.txt">Table of n, a(n) for n = 1..126</a>
%e Some solutions for n=4
%e ..2...-3...-4....4...-1...-4....4...-1...-4...-3....2...-3....4...-3...-2....4
%e .-1....1....1...-2...-3...-4...-2...-3...-2...-1...-3...-1...-4...-2...-1...-2
%e .-4....2....3...-3....2...-2...-3....2...-2...-4....4....4...-3....3...-4....3
%e ..4....1....3....4....1....1....4....3....4...-4....1...-2....2....3....1...-4
%e ..4...-2...-4...-4...-1...-2....3...-4...-1....1...-1...-2....1....3....1...-2
%e .-4...-1...-2...-3....3....1...-2....4...-2...-2....2....3....4...-3...-1...-1
%e .-2....1...-3...-4....3....1...-1....2...-3....4...-2....4...-4....2...-4....3
%K nonn
%O 1,1
%A _R. H. Hardin_ May 04 2011
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