A202251 - OEIS

%I #5 Mar 31 2012 12:36:47

%S 1,7,75,779,8211,88301,960501,10536609,116366779,1292162535,

%T 14412747241,161362353297,1812334370533,20410840535049,

%U 230416525827147,2606567584536987,29540755940559963,335338507713978229

%N Number of zero-sum -7..7 arrays of n elements with adjacent element differences also in -7..7

%C Column 7 of A202252

%H R. H. Hardin, <a href="/A202251/b202251.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=6

%e .-3....3....6...-2...-7...-5....6...-5...-5....1...-4....3....5...-2....4...-3

%e ..3....3....0...-1...-7...-2...-1....2...-1....4....3....4...-2...-5....0...-2

%e ..3...-3....1....3....0....5....3....3....2...-2....2...-2....2...-3...-6....1

%e .-4....4...-3....0....7...-1...-1...-1....2....4...-1...-6....0...-1....1...-2

%e ..3...-2...-3...-2....2....0...-3....1....0...-1....0...-1....1....6....4....1

%e .-2...-5...-1....2....5....3...-4....0....2...-6....0....2...-6....5...-3....5

%K nonn

%O 1,2

%A _R. H. Hardin_ Dec 14 2011