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%I #6 Mar 31 2012 12:36:20
%S 2,6,15,26,45,72,105,150,206,273,353,446,560,687,834,998,1182,1388,
%T 1618,1875,2156,2463,2797,3151,3551,3978,4434,4923,5448,6009,6604,
%U 7243,7925,8639,9404,10198,11051,11943,12887,13873,14909,16001,17135,18332,19584
%N Number of 1X4 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 1 zero-sum 4-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations)
%C Column (1,4,n) of A192710
%H R. H. Hardin, <a href="/A192691/b192691.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for 1X4 <= 2*4^2
%e .-1..0..0..1...-2..0..0..2...-1.-1.-1..3...-2..0..1..1...-3.-1..0..4
%K nonn
%O 1,1
%A _R. H. Hardin_ Jul 07 2011
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