%I #8 Oct 27 2019 22:33:17
%S 0,0,0,0,0,0,0,0,64,1644,19306,146718,820218,3670288,13846830,
%T 45661556,134896662,364019248,909633276,2129318414,4709083054,
%U 9912162234,19970298696,38707229282,72458290216,131476840106,231906957348
%N Number of ways to arrange 6 nonattacking queens on the lower triangle of an n X n board.
%C Column 6 of A194498.
%H R. H. Hardin, <a href="/A194496/b194496.txt">Table of n, a(n) for n = 1..35</a>
%e Some solutions for 9 X 9:
%e 0 0 0 0
%e 0 1 0 0 1 0 0 0
%e 0 0 0 1 0 0 0 0 0 0 1 0
%e 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
%e 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 1 0 0 0 0
%e 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0
%e 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0
%e 0 0 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1
%e 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0
%K nonn
%O 1,9
%A _R. H. Hardin_, Aug 26 2011
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