|
%I #5 Mar 31 2012 12:36:39
%S 52,446,3396,26850,211374,1689732,13587804,109957140,893510530,
%T 7288331916,59637096784,489325754576,4024444316206,33167657580268,
%U 273853057747366,2264784856966600,18757225819498566,155553439876468586
%N Number of -4..4 arrays x(0..n+1) of n+2 elements with zero sum and nonzero second differences
%C Column 4 of A200553
%H R. H. Hardin, <a href="/A200549/b200549.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for n=3
%e ..0....0...-3...-3...-1...-4...-1....1...-2...-3....0...-1...-1...-2....1...-3
%e ..2...-1....3....2....1...-4....3....2...-3....0....3....1....3...-3...-2....1
%e .-4....2...-4....1...-2....1....0...-4....4...-3....4...-1...-2...-3....2....3
%e ..0...-4....3....1...-1....3....2....4...-1....3...-3...-1...-1....4....1....3
%e ..2....3....1...-1....3....4...-4...-3....2....3...-4....2....1....4...-2...-4
%K nonn
%O 1,1
%A _R. H. Hardin_ Nov 19 2011
| 