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A189947 1/4 the number of arrangements of n+1 nonzero numbers x(i) in -5..5 with the sum of sign(x(i))*(|x(i)| mod x(i+1)) equal to zero 1

%I

%S 10,39,306,3247,31284,280284,2514945,23257218,219695998,2090461716,

%T 19931671853,190527865384,1828012347661,17602780129116,

%U 169999647974922,1645503998030853,15958170796668622,155032669862412399

%N 1/4 the number of arrangements of n+1 nonzero numbers x(i) in -5..5 with the sum of sign(x(i))*(|x(i)| mod x(i+1)) equal to zero

%C Column 5 of A189951

%H R. H. Hardin, <a href="/A189947/b189947.txt">Table of n, a(n) for n = 1..189</a>

%e Some solutions with n=3

%e ..1...-2...-5....2...-5....4...-1...-2....3....2...-1...-2...-1....1....4...-4

%e ..3....3....4...-2...-5...-4...-4...-1....1....4....3...-2...-4...-3...-3...-4

%e .-1...-5....1....1...-1...-4....1...-1....1...-3....1....1....1...-1...-1....2

%e .-3...-2....4....1...-1...-4....3....1...-1....4....4...-1...-4...-4....5...-2

%K nonn

%O 1,1

%A _R. H. Hardin_ May 02 2011

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Last modified September 20 19:26 EDT 2021. Contains 347588 sequences. (Running on oeis4.)