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%I #5 Mar 31 2012 12:36:46
%S 4,281,44300,8249505,1387552127,197324899476,23770010642604,
%T 2467219447235558,224555987749683857,18190414439380817926,
%U 1327557199228235157815,88165919561636605868645
%N Number of nX6 zero-sum -1..1 arrays with rows and columns lexicographically nondecreasing
%C Column 6 of A202033
%H R. H. Hardin, <a href="/A202031/b202031.txt">Table of n, a(n) for n = 1..20</a>
%e Some solutions for n=3
%e .-1.-1.-1.-1..0..1...-1.-1.-1.-1..0..1...-1.-1..0..0..1..1...-1.-1.-1..0..1..1
%e .-1.-1..1..1..0..1...-1..0..1..1..1.-1...-1..0.-1..0..1..1...-1..1..1.-1.-1..1
%e ..0..1..0..0..0..1....0..0..0..1..1..0...-1..1..1.-1.-1..1....1..1..1.-1.-1..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Dec 09 2011