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%I #5 Aug 11 2014 22:45:54
%S 42,438,3768,37984,396950,4092246,41991510,431437274,4435310118,
%T 45590703272,468598417126,4816515719528,49507271980530,
%U 508867096276696,5230454214732138,53761897206996568,552598679075230458
%N Number of black-square subarrays of (n+2)X(6+2) 0..3 arrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero
%C Column 6 of A230935
%H R. H. Hardin, <a href="/A230933/b230933.txt">Table of n, a(n) for n = 1..210</a>
%H R. H. Hardin, <a href="/A230933/a230933.txt">Empirical recurrence of order 71</a>
%F Empirical recurrence of order 71 (see link above)
%e Some solutions for n=4
%e ..x..0..x..0..x..1..x..3....x..0..x..2..x..2..x..0....x..0..x..2..x..0..x..0
%e ..3..x..1..x..2..x..0..x....1..x..3..x..3..x..1..x....3..x..1..x..3..x..1..x
%e ..x..2..x..0..x..3..x..1....x..2..x..0..x..0..x..0....x..2..x..0..x..2..x..0
%e ..1..x..3..x..1..x..2..x....1..x..3..x..1..x..3..x....1..x..1..x..1..x..3..x
%e ..x..0..x..2..x..0..x..1....x..2..x..2..x..0..x..2....x..0..x..0..x..0..x..2
%e ..3..x..3..x..3..x..3..x....1..x..1..x..3..x..3..x....3..x..3..x..3..x..3..x
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 01 2013