%I #3 Mar 31 2012 12:35:49
%S 0,168,16632,1729728,199536480,25241364720,3445446284280,
%T 500598983364480,76591644454765440,12237255920840932800,
%U 2028351316862121451200,346968438887939861076480,60995474427232155123331200
%N a(n)=0!*1!*2!*3!*(4*n)!*6*n*(n-1) / ((n)!*(n+1)!*(n+2)!*(n+3)!)
%C (Empirical) Number of nX4 matrices containing a defective permutation of 1..4*n in strictly increasing order rowwise and columnwise, with one permutation value omitted and one repeated (see example)
%C Column 4 of A181204
%H R. H. Hardin, <a href="/A181202/b181202.txt">Table of n, a(n) for n=1..50</a>
%e Some solutions for 2X4
%e ..1..3..4..5....1..2..4..5....2..4..5..7....1..2..3..4....1..3..4..6
%e ..2..5..7..8....3..5..7..8....3..6..7..8....4..5..6..8....5..6..7..8
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 10 2010