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%I A108185 #11 Apr 28 2019 15:29:24
%S A108185 0,4,24,1744,88480,20785984,4774925568,3557583518976,2784648830636544,
%T A108185 7054995406469377024,16660711592693252288512
%N A108185 Number of Cantorian n X n matrices over a 2-letter alphabet.
%C A108185 A matrix is Cantorian if no row matches any of the strings obtained by taking one term from each column in turn in such a way that they are from different rows. That is, no row word can match any transversal word.
%C A108185 More precisely, let the matrix be M = (M_ij). Then no row (M_i1, M_i2, ..., M_in) can agree with any "transversal" (M_{1, pi(1}}, ..., M_{n, pi{n}}) for any permutation pi in S_n.
%H A108185 S. Brlek, M. Mendes France, J. M. Robson and M. Rubey, <a href="http://dx.doi.org/10.5169/seals-2652">Cantorian tableaux and permanents</a>, L'Enseignement Math. 50 (2004), 287-304.
%e A108185 a(2) = 4 because the matrices [[a,a],[b,b]], [[a,b],[b,a]] and the matrices obtained by switching a with b are Cantorian.
%K A108185 hard,nonn,nice
%O A108185 1,2
%A A108185 _Jeffrey Shallit_, Jun 14 2005

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