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%I #4 Mar 31 2012 12:35:35
%S 5,104,1409,11960,85841,534816,3017385,15787165,77891237,366749318,
%T 1662432947,7302379696,31240817911,130688934607,536275945765,
%U 2164142120076,8606910817129,33793586661904,131185521194097
%N Number of slanted 4Xn (i=1..4)X(j=i..n+i-1) 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, and 4 in the lower right corner
%H R. H. Hardin, <a href="/A165387/b165387.txt">Table of n, a(n) for n=2..22</a>
%e Some solutions for n=4
%e ...1.1.2.2.........1.1.4.2.........1.1.2.2.........1.1.2.2......
%e .....1.3.2.2.........4.4.4.4.........1.3.3.3.........1.2.2.2....
%e .......3.3.2.2.........4.3.4.4.........3.3.3.3.........3.3.2.2..
%e .........3.3.3.4.........3.3.4.4.........3.3.4.4.........3.2.2.4
%e ------
%e ...1.1.2.2.........1.1.1.2.........1.2.2.2.........1.1.2.2......
%e .....1.1.2.2.........1.2.2.2.........2.2.2.2.........1.1.2.1....
%e .......1.1.2.4.........3.3.4.4.........3.3.4.4.........1.1.1.1..
%e .........3.4.4.4.........3.3.4.4.........3.4.4.4.........3.3.4.4
%e ------
%e ...1.1.1.2.........1.1.1.2.........1.1.2.2.........1.1.2.2......
%e .....1.1.3.3.........2.2.2.2.........2.2.4.4.........3.3.2.2....
%e .......1.3.4.4.........2.2.2.4.........2.2.4.4.........3.3.2.2..
%e .........3.3.4.4.........3.4.4.4.........3.4.4.4.........3.3.4.4
%K nonn
%O 2,1
%A _R. H. Hardin_ Sep 17 2009
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