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Number of arrangements of n+1 nonzero numbers x(i) in -8..8 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 #5 Mar 31 2012 12:36:19

%S 56,536,6946,92478,1291797,18951546,282859251,4232955454,63898862902,

%T 972408511316,14859125421285,227805216299376,3504714306481893,

%U 54079878634478640,836480995724826396,12965711458798193610

%N Number of arrangements of n+1 nonzero numbers x(i) in -8..8 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 8 of A190071

%H R. H. Hardin, <a href="/A190070/b190070.txt">Table of n, a(n) for n = 1..76</a>

%e Some solutions for n=4

%e ..7....8....8....5...-3...-6...-2...-2...-7....2....3...-7...-8....5....8...-3

%e ..6....3....2....8...-8....4...-3....6....8...-5...-7...-6....8....2....8....5

%e .-2....5...-4....8....6....3....6...-8....8...-3....3....8....8...-6...-4...-3

%e .-3...-8....1...-4....5....3....6....7....5....5....1....5....7....4....6...-4

%e .-6....7...-8...-7....8....6...-4....2...-4...-3...-7...-2...-7...-6....3...-6

%K nonn

%O 1,1

%A _R. H. Hardin_ May 04 2011