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%I #4 Jan 21 2013 07:31:00
%S 1,7,7279,14576404,230141263315,7575106427737240,
%T 827196295133181978340,177037611175595181692394660,
%U 86030164534670200470739520304375,75149351745335662460465241596540458600
%N Number of 6Xn arrays with each row a permutation of 1..n having at least as many downsteps as the preceding row
%C Row 6 of A221623
%H R. H. Hardin, <a href="/A221628/b221628.txt">Table of n, a(n) for n = 1..13</a>
%e Some solutions for n=3
%e ..2..3..1....1..2..3....1..3..2....1..3..2....3..1..2....1..3..2....3..1..2
%e ..1..3..2....1..2..3....2..1..3....1..3..2....3..1..2....2..3..1....1..3..2
%e ..3..1..2....2..1..3....2..3..1....2..3..1....1..3..2....2..1..3....2..1..3
%e ..1..3..2....2..3..1....2..1..3....2..3..1....1..3..2....3..1..2....2..1..3
%e ..2..3..1....3..1..2....1..3..2....3..1..2....2..1..3....2..3..1....2..1..3
%e ..3..1..2....2..3..1....2..3..1....2..3..1....2..3..1....1..3..2....3..2..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 21 2013
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