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A251244 Number of (n+1)X(3+1) 0..2 arrays with no 2X2 subblock having the sum of its diagonal elements less than the minimum of its antidiagonal elements.

%I A251244 #6 Jul 23 2025 13:12:08
%S A251244 5139,327753,20904689,1333268433,85032883789,5423196612609,
%T A251244 345878548314469,22059307525808241,1406889917539387453,
%U A251244 89728076602595409057,5722642281407762900517,364976447934805630538193
%N A251244 Number of (n+1)X(3+1) 0..2 arrays with no 2X2 subblock having the sum of its diagonal elements less than the minimum of its antidiagonal elements.
%C A251244 Column 3 of A251249
%H A251244 R. H. Hardin, <a href="/A251244/b251244.txt">Table of n, a(n) for n = 1..210</a>
%F A251244 Empirical: a(n) = 81*a(n-1) -1165*a(n-2) +4257*a(n-3) -544*a(n-4) -4428*a(n-5) +7512*a(n-6) -80352*a(n-7) -67376*a(n-8) +32256*a(n-9) +20160*a(n-10)
%e A251244 Some solutions for n=1
%e A251244 ..2..1..1..2....1..2..2..0....2..2..0..0....0..2..2..1....0..2..2..0
%e A251244 ..0..2..0..2....0..0..0..1....1..0..0..2....1..2..0..2....0..1..2..2
%K A251244 nonn
%O A251244 1,1
%A A251244 _R. H. Hardin_, Dec 01 2014