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%I #5 Mar 31 2012 12:36:20
%S 2,6,14,29,56,101,166,267,407,604,865,1211,1659,2236,2956,3861,4949,
%T 6299,7906,9849,12120,14817,17958,21641,25859,30753,36318,42732,49917,
%U 58116,67296,77693,89219,102175,116527,132515,150117,169602,191013,214662
%N Number of 5X2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 5 zero-sum 2-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations)
%C Column (5,2,n) of A192710
%H R. H. Hardin, <a href="/A192705/b192705.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for 5X2 <= 2*4^2
%e .-3..3...-2..2...-2..2...-1..1...-1..1...-2..2...-3..3...-3..3...-3..3...-2..2
%e .-1..1...-1..1...-2..2...-1..1...-1..1...-2..2...-1..1....0..0...-1..1...-2..2
%e .-1..1...-1..1...-1..1....0..0...-1..1...-2..2...-1..1....0..0....0..0...-2..2
%e .-1..1....0..0...-1..1....0..0....0..0...-2..2...-1..1....0..0....0..0....0..0
%e .-1..1....0..0...-1..1....0..0....0..0....0..0....0..0....0..0....0..0....0..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jul 07 2011
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