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A190067 Number of arrangements of n+1 nonzero numbers x(i) in -5..5 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 1

%I

%S 20,143,1126,9904,88509,834717,7843113,73725405,697624797,6644826507,

%T 63556636483,609902716100,5871497904831,56683948490522,

%U 548487091412193,5317814454716839,51651465543152430,502495332741155890

%N Number of arrangements of n+1 nonzero numbers x(i) in -5..5 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 Column 5 of A190071

%H R. H. Hardin, <a href="/A190067/b190067.txt">Table of n, a(n) for n = 1..137</a>

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ May 04 2011

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Last modified December 2 08:18 EST 2020. Contains 338868 sequences. (Running on oeis4.)