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A251262 Number of (n+1) X (2+1) 0..1 arrays with no 2 X 2 subblock having x11-x00 less than x10-x01.

%I A251262 #7 Nov 27 2018 11:37:20
%S A251262 26,114,480,2058,8812,37772,161906,694042,2975162,12753740,54671978,
%T A251262 234364684,1004661088,4306723662,18461816670,79141059954,339257370296,
%U A251262 1454309095546,6234249070708,26724622430876,114561583275826
%N A251262 Number of (n+1) X (2+1) 0..1 arrays with no 2 X 2 subblock having x11-x00 less than x10-x01.
%H A251262 R. H. Hardin, <a href="/A251262/b251262.txt">Table of n, a(n) for n = 1..210</a>
%F A251262 Empirical: a(n) = 5*a(n-1) - 2*a(n-2) - 5*a(n-3) + 2*a(n-4).
%F A251262 Empirical g.f.: 2*x*(13 - 8*x - 19*x^2 + 8*x^3) / (1 - 5*x + 2*x^2 + 5*x^3 - 2*x^4). - _Colin Barker_, Nov 27 2018
%e A251262 Some solutions for n=4:
%e A251262 ..0..1..0....1..1..1....1..1..1....0..0..0....0..1..0....1..0..1....0..1..1
%e A251262 ..1..0..1....0..1..1....0..1..1....0..0..0....0..0..1....0..1..1....1..1..1
%e A251262 ..0..1..1....0..0..0....0..0..0....1..1..1....0..1..0....0..1..1....0..0..1
%e A251262 ..0..0..0....0..0..0....0..0..1....0..1..1....0..0..1....0..1..1....0..0..1
%e A251262 ..1..1..1....0..1..1....0..1..1....1..1..1....1..1..0....1..0..0....0..1..1
%Y A251262 Column 2 of A251268.
%K A251262 nonn
%O A251262 1,1
%A A251262 _R. H. Hardin_, Dec 01 2014