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A251145 Number of (n+1) X (4+1) 0..2 arrays with every 2 X 2 subblock summing to 4 and no 2 X 2 subblock having exactly two nonzero entries.

%I A251145 #16 Nov 26 2018 11:23:38
%S A251145 107,161,247,401,667,1141,1987,3521,6327,11521,21227,39541,74387,
%T A251145 141201,270167,520561,1009147,1966581,3849507,7563681,14908407,
%U A251145 29462561,58351947,115776501,230052467,457677041,911425687,1816495121,3622705627
%N A251145 Number of (n+1) X (4+1) 0..2 arrays with every 2 X 2 subblock summing to 4 and no 2 X 2 subblock having exactly two nonzero entries.
%H A251145 R. H. Hardin, <a href="/A251145/b251145.txt">Table of n, a(n) for n = 1..210</a>
%F A251145 Empirical: a(n) = 3*a(n-1) - 5*a(n-3) + a(n-4) + 2*a(n-5).
%F A251145 Empirical g.f.: x*(107 - 160*x - 236*x^2 + 195*x^3 + 162*x^4) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 - x - x^2)). - _Colin Barker_, Nov 26 2018
%e A251145 Some solutions for n=4:
%e A251145 ..0..1..0..1..0....1..2..0..2..0....0..2..1..2..0....0..2..0..2..0
%e A251145 ..1..2..1..2..1....0..1..1..1..1....1..1..0..1..1....1..1..1..1..1
%e A251145 ..0..1..0..1..0....1..2..0..2..0....1..1..2..1..1....1..1..1..1..1
%e A251145 ..1..2..1..2..1....0..1..1..1..1....1..1..0..1..1....0..2..0..2..0
%e A251145 ..0..1..0..1..0....2..1..1..1..1....1..1..2..1..1....1..1..1..1..1
%Y A251145 Column 4 of A251149.
%K A251145 nonn
%O A251145 1,1
%A A251145 _R. H. Hardin_, Nov 30 2014