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Number of n X 4 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 5 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 #7 Apr 05 2020 22:17:23

%S 15,104,708,4917,33297,204206,1108382,5361624,23477312,94474684,

%T 353596604,1242207201,4125406694,13026205724,39292608858,113681479364,

%U 316556625809,850933663116,2213918991347,5587988935294,13711077238915

%N Number of n X 4 0,1 arrays indicating 2 X 2 subblocks of some larger (n+1) X 5 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 4 of A227333.

%H R. H. Hardin, <a href="/A227331/b227331.txt">Table of n, a(n) for n = 1..210</a>

%H R. H. Hardin, <a href="/A227331/a227331.txt">Empirical polynomial of degree 31</a>

%F Empirical polynomial of degree 31 (see link above).

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jul 07 2013