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Number of n X 5 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 6 binary array having two adjacent 1's and two adjacent 0's, with rows and columns of the latter in lexicographically nondecreasing order.
1

%I #6 Apr 05 2020 22:19:07

%S 26,285,3013,33297,366606,3774137,35026386,290742258,2174611745,

%T 14827903973,93194118189,544831575434,2984722060733,15415176834304,

%U 75441255758231,351377507165460,1563422116701546,6667161613820532

%N Number of n X 5 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 6 binary array having two adjacent 1's and two adjacent 0's, with rows and columns of the latter in lexicographically nondecreasing order.

%C Column 5 of A227333.

%H R. H. Hardin, <a href="/A227332/b227332.txt">Table of n, a(n) for n = 1..56</a>

%e Some solutions for n=4

%e ..0..0..0..0..0....0..0..0..1..1....0..1..0..0..0....0..0..0..0..1

%e ..0..0..0..0..0....0..0..1..0..0....1..0..1..1..0....0..1..0..0..0

%e ..1..1..0..1..0....0..0..0..1..0....1..0..0..0..0....0..0..0..1..1

%e ..1..0..0..1..0....1..1..0..0..1....1..0..0..0..0....0..0..0..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Jul 07 2013