%I #8 Oct 27 2019 22:12:18
%S 0,0,0,0,0,0,0,0,0,10,1210,27198,322782,2564988,15372702,74615814,
%T 306900410,1105651074,3569169990,10512880400,28628691842,72880455042,
%U 174895586328,398556484840,867314768878,1811576604968,3646385889888
%N Number of ways to arrange 7 nonattacking queens on the lower triangle of an n X n board.
%C Column 7 of A194498.
%H R. H. Hardin, <a href="/A194497/b194497.txt">Table of n, a(n) for n = 1..28</a>
%e Some solutions for 10 X 10:
%e 0 0 0
%e 0 0 0 0 0 0
%e 0 0 0 0 0 0 0 0 0
%e 0 1 0 0 0 1 0 0 0 0 0 1
%e 0 0 0 1 0 0 0 0 1 0 1 0 0 0 0
%e 1 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0
%e 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1 0
%e 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0
%e 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0
%e 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0
%K nonn
%O 1,10
%A _R. H. Hardin_, Aug 26 2011