%I
%S 0,0,0,0,0,16,20,128,396,2288,11152,65712,437848,3118664,23387448,
%T 183463680,1474699536
%N Number of ways to place n+1 queens and a pawn on an n X n board so that no two queens attack each other.
%H R. D. Chatham, <a href="http://people.moreheadstate.edu/fs/d.chatham/n+kqueens.html">The N+k Queens Problem Page</a>.
%H R. D. Chatham, M. Doyle, G. H. Fricke, J. Reitmann, R. D. Skaggs and M. Wolff, <a href="http://people.moreheadstate.edu/fs/d.chatham/QueensSep2.pdf">Independence and Domination Separation in Chessboard Graphs</a>, Journal of Combinatorial Mathematics and Combinatorial Computing, to appear.
%H R. D. Chatham, G. H. Fricke and R. D. Skaggs, <a href="http://people.moreheadstate.edu/fs/d.chatham/queenssep.pdf">The Queens Separation Problem</a>, Utilitas Mathematica 69 (2006), 129-141.
%e a(4) = 0 because when 5 queens are placed on a 4 X 4 board, at least 2 queens will be adjacent and therefore mutually attacking.
%Y Cf. A000170 A103331.
%K more,nonn
%O 1,6
%A R. Douglas Chatham (d.chatham(AT)moreheadstate.edu), Jan 31 2005
%E Further terms from R. Douglas Chatham (d.chatham(AT)moreheadstate.edu), Feb 15 2005, Apr 20 2007, Apr 28 2007
%E a(12) corrected by R. Douglas Chatham (d.chatham(AT)moreheadstate.edu), May 12 2009
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