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%I #5 Mar 31 2012 12:36:16
%S 16,75,889,13034,168737,2095080,26586582,346371666,4569825052,
%T 60616719909,807520929855,10805101528251,145152790595820,
%U 1956318942197183,26437935517478725,358117322511949885
%N 1/4 the number of arrangements of n+1 nonzero numbers x(i) in -7..7 with the sum of sign(x(i))*(|x(i)| mod x(i+1)) equal to zero
%C Column 7 of A189951
%H R. H. Hardin, <a href="/A189949/b189949.txt">Table of n, a(n) for n = 1..96</a>
%e Some solutions with n=3
%e .-5....7....1...-6...-6....6...-1....4....1....2...-4...-3....7....1...-1...-3
%e .-2....6....3....6....2....1....2...-7....7...-6...-4....2...-6...-3....3....1
%e ..1...-1...-2...-5...-6...-7...-7...-5...-2....4...-2...-4...-1...-3....1...-3
%e .-7...-3...-4...-2...-4...-3....6...-3...-6...-1....2...-3....3....2....5....2
%K nonn
%O 1,1
%A _R. H. Hardin_ May 02 2011
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