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%I #5 Mar 31 2012 12:36:24
%S 505623,839301197,122092290831,5151383545261,103074513713971,
%T 1252997799222737,10665939121760907,69488770600802237,
%U 367679036207885407,1647079991451268941,6438544930173240123,22466897655527435065
%N Number of lower triangles of a 7X7 -n..n array with all row and column sums zero
%C Row 7 of A195522
%H R. H. Hardin, <a href="/A195525/b195525.txt">Table of n, a(n) for n = 1..14</a>
%e Some solutions for n=4
%e ..0..............0..............0..............0..............0
%e .-4.4...........-4.4............3-3...........-2.2...........-4.4
%e ..1.2-3..........2-3.1..........3-2-1.........-2.1.1.........-2.0.2
%e ..4-1-1-2.......-3-3.3.3........2-1.1-2.......-4-1.1.4........4.3-3-4
%e .-1-1.2.2-2......3-3-1-1.2.....-2.2.1.3-4......3-2.2.0-3.....-1-4-3.4.4
%e .-2-3.2-1.3.1...-1.3-3.0-3.4...-2.3.2-4.4-3....2-4.0-1.2.1....1.0.0.3-3-1
%e ..2-1.0.1-1-1.0..3.2.0-2.1-4.0.-4.1-3.3.0.3.0..3.4-4-3.1-1.0..2-3.4-3-1.1.0
%K nonn
%O 1,1
%A _R. H. Hardin_ Sep 20 2011
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