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A251224 Number of (n+1)X(4+1) 0..1 arrays with no 2X2 subblock having the minimum of its diagonal elements greater than the absolute difference of its antidiagonal elements.

%I A251224 #6 Jul 23 2025 13:11:35
%S A251224 597,11753,228689,4462968,87024544,1697323707,33102432698,
%T A251224 645599385182,12591115117932,245564664777825,4789248769819459,
%U A251224 93404749891139903,1821673395009104814,35528107366814113243,692904893934316841530
%N A251224 Number of (n+1)X(4+1) 0..1 arrays with no 2X2 subblock having the minimum of its diagonal elements greater than the absolute difference of its antidiagonal elements.
%C A251224 Column 4 of A251228
%H A251224 R. H. Hardin, <a href="/A251224/b251224.txt">Table of n, a(n) for n = 1..210</a>
%F A251224 Empirical: a(n) = 13*a(n-1) +150*a(n-2) -269*a(n-3) -3713*a(n-4) +1325*a(n-5) +30575*a(n-6) -16105*a(n-7) -99760*a(n-8) +117265*a(n-9) +20076*a(n-10) -71217*a(n-11) +11160*a(n-12) +14210*a(n-13) -3935*a(n-14) -1079*a(n-15) +396*a(n-16) +60*a(n-17)
%e A251224 Some solutions for n=2
%e A251224 ..1..1..1..0..1....0..0..0..0..0....0..1..0..1..1....1..0..1..1..1
%e A251224 ..0..1..0..0..1....0..0..1..1..1....0..1..0..0..1....1..1..0..1..0
%e A251224 ..1..1..1..0..1....1..0..0..0..0....0..1..1..1..0....0..1..1..0..0
%K A251224 nonn
%O A251224 1,1
%A A251224 _R. H. Hardin_, Nov 30 2014