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A251127 Number of (n+1) X (7+1) 0..1 arrays with no 2 X 2 subblock having the sum of its diagonal elements greater than the maximum of its antidiagonal elements.

%I A251127 #10 Nov 26 2018 06:56:00
%S A251127 354,510,680,938,1268,1743,2420,3429,4957,7321,11025,16890,26241,
%T A251127 41224,65310,104116,166730,267857,431290,695527,1122859,1814075,
%U A251127 2932255,4741268,7668063,12403458,20065220,32461934,52519952,84974211,137486000
%N A251127 Number of (n+1) X (7+1) 0..1 arrays with no 2 X 2 subblock having the sum of its diagonal elements greater than the maximum of its antidiagonal elements.
%H A251127 R. H. Hardin, <a href="/A251127/b251127.txt">Table of n, a(n) for n = 1..210</a>
%F A251127 Empirical: a(n) = 4*a(n-1) - 5*a(n-2) + a(n-3) + 2*a(n-4) - a(n-5) for n>6.
%F A251127 Empirical g.f.: x*(354 - 906*x + 410*x^2 + 414*x^3 - 302*x^4 + 15*x^5) / ((1 - x)^3*(1 - x - x^2)). - _Colin Barker_, Nov 26 2018
%e A251127 Some solutions for n=4:
%e A251127 ..0..0..0..0..0..0..0..1....0..0..0..1..0..1..0..1....0..0..0..0..0..0..1..0
%e A251127 ..0..0..0..0..0..0..0..1....0..0..0..1..0..1..0..0....0..0..0..0..0..0..1..0
%e A251127 ..0..0..0..0..0..0..0..1....0..0..0..1..0..1..0..0....0..0..0..0..0..0..1..0
%e A251127 ..1..1..1..1..1..1..1..1....0..0..0..1..0..1..0..0....0..0..0..0..0..0..1..0
%e A251127 ..1..0..0..0..0..0..0..0....0..0..0..1..0..1..0..0....1..1..1..1..1..1..1..0
%Y A251127 Column 7 of A251128.
%K A251127 nonn
%O A251127 1,1
%A A251127 _R. H. Hardin_, Nov 30 2014