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%I #4 Nov 30 2014 07:10:35
%S 526,3616,19131,99147,549944,3097574,17154384,94541640,523362695,
%T 2902098174,16074820995,88991683894,492794584784,2729305867906,
%U 15115136455485,83704974778717,463549806671218,2567128453854706
%N Number of (n+1)X(3+1) 0..2 arrays with no 2X2 subblock having the maximum of its diagonal elements greater than the absolute difference of its antidiagonal elements
%C Column 3 of A251113
%H R. H. Hardin, <a href="/A251108/b251108.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 21*a(n-1) -208*a(n-2) +1340*a(n-3) -6378*a(n-4) +23759*a(n-5) -71215*a(n-6) +174232*a(n-7) -350668*a(n-8) +582938*a(n-9) -801786*a(n-10) +912272*a(n-11) -856248*a(n-12) +658631*a(n-13) -408814*a(n-14) +196251*a(n-15) -63460*a(n-16) +5494*a(n-17) +6902*a(n-18) -3702*a(n-19) +790*a(n-20) -368*a(n-21) +453*a(n-22) -295*a(n-23) +89*a(n-24) -7*a(n-25) -a(n-26) for n>27
%e Some solutions for n=4
%e ..0..0..0..1....0..0..1..2....1..1..1..2....1..0..2..2....0..0..1..2
%e ..2..0..0..0....0..0..1..1....0..0..0..2....1..1..0..1....0..0..1..0
%e ..2..2..2..0....0..0..0..0....0..0..0..2....0..1..0..0....0..0..1..1
%e ..0..0..2..0....2..2..0..0....1..1..0..2....0..1..1..0....1..1..0..0
%e ..1..0..2..1....0..2..0..0....0..1..0..2....2..0..1..0....2..1..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 30 2014