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A189946 1/4 the number of arrangements of n+1 nonzero numbers x(i) in -4..4 with the sum of sign(x(i))*(|x(i)| mod x(i+1)) equal to zero 1

%I

%S 8,29,159,1246,9884,73992,542353,4014514,30195535,229483051,

%T 1753032755,13435104833,103277494510,796249956004,6155156882177,

%U 47687937106356,370185895527595,2878540976279306,22417566580905998,174824418896006501

%N 1/4 the number of arrangements of n+1 nonzero numbers x(i) in -4..4 with the sum of sign(x(i))*(|x(i)| mod x(i+1)) equal to zero

%C Column 4 of A189951

%H R. H. Hardin, <a href="/A189946/b189946.txt">Table of n, a(n) for n = 1..200</a>

%e Some solutions with n=3

%e ..1....3...-4....2...-2...-1....4...-1....2....4...-3....1....1....4...-4...-1

%e .-1....1....4....2...-1....3...-2...-3....2...-4....2...-2....3...-2....3....3

%e .-1...-4....4....1...-1....2....1....3....2....2....1...-1...-2....2....3....1

%e ..1...-3....2....1...-1...-1....1....2...-2....1....4...-2....4....1....2...-2

%K nonn

%O 1,1

%A _R. H. Hardin_ May 02 2011

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Last modified March 23 12:43 EDT 2019. Contains 321430 sequences. (Running on oeis4.)