A201491 - OEIS

%I #5 Mar 31 2012 12:36:44

%S 5,226,9331,301432,7798656,168357815,3127432827,51118964623,

%T 747555368709,9907361072523,120219907134113,1346895312283777,

%U 14030077787811997,136685387878719346,1251770455347161910,10823892860244631974

%N Number of nX3 zero-sum -2..2 arrays with rows and columns lexicographically nondecreasing

%C Column 3 of A201496

%H R. H. Hardin, <a href="/A201491/b201491.txt">Table of n, a(n) for n = 1..90</a>

%e Some solutions for n=3

%e .-2..1..1...-2.-1.-1...-1.-1..1...-2.-1..2...-2..1..2...-2.-1..2...-2..0..0

%e .-2..1..1....0..0..0....1..2.-2...-1..0..1....0.-1..1...-2..1..1...-1.-1.-1

%e ..0.-2..2....2..0..2....2..0.-2....1.-1..1....2.-1.-2...-1..1..1....1..2..2

%K nonn

%O 1,1

%A _R. H. Hardin_ Dec 02 2011