cp's OEIS Frontend

A189505 Number of arrangements of 9 nonzero numbers x(i) in -n..n with the sum of floor(x(i)/x(i+1)) equal to zero.

%I A189505 #7 Jul 22 2025 11:48:05
%S A189505 140,26816,852940,10077438,67449574,326423068,1218634086,3870426602,
%T A189505 10678039872,26541186546,60515390904,129217908546,258501393812,
%U A189505 493822993858,903540678414,1589111278140,2702453254684,4467233004764
%N A189505 Number of arrangements of 9 nonzero numbers x(i) in -n..n with the sum of floor(x(i)/x(i+1)) equal to zero.
%C A189505 Row 8 of A189498
%H A189505 R. H. Hardin, <a href="/A189505/b189505.txt">Table of n, a(n) for n = 1..58</a>
%e A189505 Some solutions for n=5
%e A189505 .-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5
%e A189505 .-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5
%e A189505 .-4...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-5...-4...-5
%e A189505 .-5....3....4....1...-1....3...-1....3...-4....2....5...-4...-1....3...-3....4
%e A189505 .-2....2....5...-1...-5...-5....1....3...-5...-3...-4...-4....1....3...-2....4
%e A189505 ..4....5...-3...-1....4...-4...-5...-4....5...-2...-5...-3....4...-5....3...-3
%e A189505 .-1....5...-2....4...-2....3....2....3....2...-1...-2....3....5....4....3....3
%e A189505 ..2...-5...-5....2....5....5...-2...-3...-5...-2...-5...-1...-1....3...-5....1
%e A189505 ..1....5...-5....1...-4....2....4...-1....2....2....5....3....1....2....2...-1
%K A189505 nonn
%O A189505 1,1
%A A189505 _R. H. Hardin_ Apr 23 2011