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%I #5 Mar 31 2012 12:36:58
%S 144,1296,11664,104976,944784,8503056,76527504,688747536,6198727824,
%T 55788550416,502096953744,4518872583696,40669853253264,
%U 366028679279376,3294258113514384,29648323021629456,266834907194665104
%N Number of (n+1)X2 0..3 arrays with no 2X2 subblock having equal diagonal elements or equal antidiagonal elements
%C Column 1 of A203826
%H R. H. Hardin, <a href="/A203819/b203819.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 16*9^n
%e Some solutions for n=4
%e ..2..0....3..2....1..0....1..1....1..1....1..0....1..3....2..0....1..0....0..2
%e ..2..3....0..1....1..0....3..2....2..0....3..3....0..2....2..0....1..2....0..3
%e ..0..1....0..2....3..2....3..0....2..3....0..1....3..1....1..0....3..2....0..2
%e ..2..3....0..1....3..0....1..1....1..0....0..1....2..0....3..2....0..0....0..3
%e ..2..3....2..1....1..0....2..2....3..2....3..2....1..0....3..2....3..1....1..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 06 2012
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