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A250969 Number of (n+1)X(4+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 A250969 #6 Jul 23 2025 12:55:23
%S A250969 604,12281,249921,5089900,103684186,2112130109,43025963570,
%T A250969 876479703950,17854730951799,363717955042320,7409282841342444,
%U A250969 150934183848595064,3074673806193093731,62634048639412217021,1275915526747412367745
%N A250969 Number of (n+1)X(4+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 A250969 Column 4 of A250973
%H A250969 R. H. Hardin, <a href="/A250969/b250969.txt">Table of n, a(n) for n = 1..210</a>
%F A250969 Empirical: a(n) = 32*a(n-1) -322*a(n-2) +2227*a(n-3) -12086*a(n-4) +47762*a(n-5) -142463*a(n-6) +321616*a(n-7) -516143*a(n-8) +570208*a(n-9) -437734*a(n-10) +223620*a(n-11) -61118*a(n-12) +2048*a(n-13) -581*a(n-14) +2307*a(n-15) -712*a(n-16) +60*a(n-17)
%e A250969 Some solutions for n=2
%e A250969 ..1..0..1..1..0....0..1..1..0..1....1..0..1..0..0....0..1..1..0..1
%e A250969 ..1..1..0..1..0....1..1..1..0..1....1..0..1..0..0....1..0..1..1..0
%e A250969 ..0..1..0..1..1....0..0..0..1..1....0..1..0..0..0....0..1..0..0..1
%K A250969 nonn
%O A250969 1,1
%A A250969 _R. H. Hardin_, Nov 29 2014