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Number of 4X3 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 4 zero-sum 3-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations)
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%I #5 Mar 31 2012 12:36:20

%S 2,10,45,191,639,1925,5059,12197,27061,55957,109220,204227,361922,

%T 621790,1032797,1662821,2607574,4007507,5999290,8835971,12784870,

%U 18186200,25491781,35326689,48192368,65114102,87009836,115061673,150717188

%N Number of 4X3 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 4 zero-sum 3-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations)

%C Column (4,3,n) of A192710

%H R. H. Hardin, <a href="/A192704/b192704.txt">Table of n, a(n) for n = 1..63</a>

%e Some solutions for 4X3 <= 2*4^2

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jul 07 2011