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%I #6 Mar 31 2012 12:36:19
%S 0,12,166,3481,88509,2783714,101530262,4232955454,198636188057,
%T 10408538943146,603033909983829,38103929980500423,2608648993698684772,
%U 193359775333060165517,15364574547397697984616,1301880431718317296701496
%N Number of arrangements of n+1 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 Diagonal of A190071
%H R. H. Hardin, <a href="/A190063/b190063.txt">Table of n, a(n) for n = 1..21</a>
%e Some solutions for n=4
%e ..4...-1...-2....1...-1...-4....4...-3...-2...-4...-3...-3....4...-1....2...-2
%e ..4...-2...-1....1....2...-4....1...-2...-3....2....1....4....2....1....2...-1
%e .-2....1...-2....3...-4...-2...-3...-1...-4....2...-4...-2...-2...-1....2...-3
%e .-1....3....2...-4....4....1....2....3....2...-2...-2...-1....2...-2....4....2
%e ..1....2...-1....4....2...-1...-1...-1....3...-1...-2...-2...-4...-2...-2...-2
%K nonn
%O 1,2
%A _R. H. Hardin_ May 04 2011
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