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A251242 Number of (n+1)X(n+1) 0..2 arrays with no 2X2 subblock having the sum of its diagonal elements less than the minimum of its antidiagonal elements.

%I A251242 #7 Jul 23 2025 13:12:01
%S A251242 75,14265,20904689,236035946835,20534495636679387,
%T A251242 13764744150100667222985,71093648993125363900542904561,
%U A251242 2829255370682961509218005180234886323
%N A251242 Number of (n+1)X(n+1) 0..2 arrays with no 2X2 subblock having the sum of its diagonal elements less than the minimum of its antidiagonal elements.
%C A251242 Diagonal of A251249
%H A251242 R. H. Hardin, <a href="/A251242/b251242.txt">Table of n, a(n) for n = 1..11</a>
%e A251242 Some solutions for n=2
%e A251242 ..2..0..0....0..2..1....2..0..2....1..2..0....2..0..1....2..2..0....1..1..0
%e A251242 ..1..2..0....0..0..1....1..1..2....1..2..0....2..1..2....1..2..1....2..2..1
%e A251242 ..2..1..0....0..0..2....0..0..0....1..1..1....1..1..0....1..1..2....1..0..2
%K A251242 nonn
%O A251242 1,1
%A A251242 _R. H. Hardin_, Dec 01 2014