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A231833 Number of n X 2 0..3 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors.

%I A231833 #7 Oct 01 2018 06:27:45
%S A231833 4,50,422,3823,34350,308419,2771101,24892609,223618304,2008825312,
%T A231833 18045827096,162110668160,1456284886944,13082209530648,
%U A231833 117521102664489,1055724534522884,9483865176690522,85196181144951446,765340833781554407
%N A231833 Number of n X 2 0..3 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors.
%H A231833 R. H. Hardin, <a href="/A231833/b231833.txt">Table of n, a(n) for n = 1..210</a>
%F A231833 Empirical: a(n) = 4*a(n-1) + 34*a(n-2) + 86*a(n-3) + 91*a(n-4) + 46*a(n-5) + 11*a(n-6) + a(n-7).
%F A231833 Empirical g.f.: x*(2 + x)*(2 + 4*x + x^2)*(1 + 6*x + 5*x^2 + x^3) / (1 - 4*x - 34*x^2 - 86*x^3 - 91*x^4 - 46*x^5 - 11*x^6 - x^7). - _Colin Barker_, Oct 01 2018
%e A231833 Some solutions for n=7:
%e A231833 ..0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0
%e A231833 ..2..2....2..2....0..0....0..0....0..0....2..0....0..2....0..0....0..0....2..0
%e A231833 ..2..3....2..3....1..0....0..0....2..0....0..0....0..0....0..0....0..3....0..0
%e A231833 ..3..3....2..2....0..0....1..3....0..2....3..1....3..2....0..1....0..0....0..0
%e A231833 ..2..2....3..1....1..3....2..2....2..2....1..1....2..2....2..2....1..3....3..2
%e A231833 ..1..0....1..1....2..2....2..1....3..2....3..3....3..1....3..3....0..0....2..2
%e A231833 ..0..1....3..3....0..0....1..1....1..1....0..0....1..3....2..2....0..3....1..1
%Y A231833 Column 2 of A231839.
%K A231833 nonn
%O A231833 1,1
%A A231833 _R. H. Hardin_, Nov 14 2013