%I A140393
%S A140393 1,0,0,2,10,4,40,92,352,724,2680,14200,73712,365596,2279184,14772512,
%T A140393 95815104,666090624,4968057848,39029188884,314666222712,2691008701644,
%U A140393 24233937684440,226732487925864
%N A140393 Number of ways of placing n nonattacking queens on n X n board (version 
               computed by NQueens(AT)home).
%C A140393 This is a new calculation of A000170 which produced a different answer 
               for n=24. I do not know which version is correct and I have therefore 
               created this second entry for the values found by the NQueens(AT)home 
               team. See the main entry for this sequence, A000170, for many further 
               references and comments.
%C A140393 As discovered on Nov 07, 2008, this sequence is likely to suffer from 
               an overflow error in the implementation of the NQueens(AT)Home project. 
               The results differ by 781684047872 = 0xb600000000.
%H A140393 NQuens(AT)home, <a href="http://nqueens.ing.udec.cl/">Home Page</a>
%Y A140393 See A000170 for further information.
%Y A140393 Sequence in context: A102512 A029673 A054790 this_sequence A000170 A038216 
               A145911
%Y A140393 Adjacent sequences: A140390 A140391 A140392 this_sequence A140394 A140395 
               A140396
%K A140393 nonn
%O A140393 1,4
%A A140393 N. J. A. Sloane (njas(AT)research.att.com), Jun 18 2008
%E A140393 a(24) is probably mistaken. - Thomas B. Preusser (thomas.preusser(AT)tu-dresden.de), 
               Nov 07 2008