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A250968 Number of (n+1)X(3+1) 0..1 arrays with no 2X2 subblock having the sum of its diagonal elements less than the absolute difference of its antidiagonal elements.

%I A250968 #6 Jul 23 2025 12:55:15
%S A250968 172,1945,22048,249921,2833397,32124018,364210219,4129278507,
%T A250968 46816221866,530784935436,6017842440934,68228062145830,
%U A250968 773544424316648,8770159340495832,99432808820402153,1127332250873994176
%N A250968 Number of (n+1)X(3+1) 0..1 arrays with no 2X2 subblock having the sum of its diagonal elements less than the absolute difference of its antidiagonal elements.
%C A250968 Column 3 of A250973
%H A250968 R. H. Hardin, <a href="/A250968/b250968.txt">Table of n, a(n) for n = 1..210</a>
%F A250968 Empirical: a(n) = 16*a(n-1) -68*a(n-2) +210*a(n-3) -492*a(n-4) +705*a(n-5) -675*a(n-6) +389*a(n-7) -120*a(n-8) +20*a(n-9)
%e A250968 Some solutions for n=3
%e A250968 ..0..1..0..1....0..1..0..1....1..1..1..0....1..0..0..1....1..0..0..0
%e A250968 ..0..1..0..1....1..0..0..1....0..1..1..1....1..1..1..1....0..1..1..1
%e A250968 ..1..0..0..1....1..1..1..1....1..1..1..0....1..0..1..0....0..1..1..0
%e A250968 ..0..1..1..0....0..1..0..1....0..0..0..0....0..0..1..1....0..1..1..0
%K A250968 nonn
%O A250968 1,1
%A A250968 _R. H. Hardin_, Nov 29 2014