|
%I #5 Mar 31 2012 12:36:39
%S 14,76,280,1240,4978,21626,91058,393660,1686980,7309386,31632968,
%T 137600876,599055566,2615427970,11433493630,50075195034,219589525108,
%U 964264276780,4238966033150,18655002576606,82175337524524
%N Number of -2..2 arrays x(0..n+1) of n+2 elements with zero sum and nonzero second differences
%C Column 2 of A200553
%H R. H. Hardin, <a href="/A200547/b200547.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for n=3
%e ..2....1....0....0...-2...-1....1....0....0....1...-2...-2...-1....0...-1....2
%e ..0...-1....2...-2....1....1....0....2...-2....1....1...-1....2....0...-1...-1
%e .-1....1...-1....0...-1....0...-2...-2....2...-2....1....1....2...-1....1...-2
%e .-1...-1...-1....0....1....2...-1...-2...-1....2....0....0...-1....2....2....0
%e ..0....0....0....2....1...-2....2....2....1...-2....0....2...-2...-1...-1....1
%K nonn
%O 1,1
%A _R. H. Hardin_ Nov 19 2011
| 