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A190066 Number of arrangements of n+1 nonzero numbers x(i) in -4..4 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.

%I A190066 #7 Jul 22 2025 12:00:12
%S A190066 12,76,483,3481,25306,191456,1436962,10802667,81709584,622881909,
%T A190066 4769974211,36631166224,282173132213,2179898773167,16878487835945,
%U A190066 130935467642770,1017555976447868,7920656405513158,61741451812499715
%N A190066 Number of arrangements of n+1 nonzero numbers x(i) in -4..4 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 A190066 Column 4 of A190071
%H A190066 R. H. Hardin, <a href="/A190066/b190066.txt">Table of n, a(n) for n = 1..200</a>
%e A190066 Some solutions for n=5
%e A190066 ..3...-2....2....3...-1....3...-1...-2...-4...-1...-1....3...-1....1...-3....4
%e A190066 .-1....2....2....3...-2...-3....2...-4...-4....2...-4....3....2....4....4...-2
%e A190066 .-2....3...-4...-3...-4...-1....3...-1....3....4....1....3...-4...-3...-3....3
%e A190066 .-2....3....4...-2...-4....2....1....2....1....2....2...-3....3....3...-4....2
%e A190066 .-1...-2....3....3....2...-4...-1...-4...-4....2....2....3....1...-4...-2....1
%e A190066 ..3...-4...-2...-2...-2....4....1....1....3...-1....1....4....2...-2....2...-4
%K A190066 nonn
%O A190066 1,1
%A A190066 _R. H. Hardin_ May 04 2011