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A258558 Number of (5+1) X (n+1) 0..1 arrays with every 2 X 2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically. 1

%I

%S 480,1329,2384,3754,5070,6662,8612,10720,12831,15045,17532,20200,

%T 22894,25714,28830,32150,35519,39037,42874,46938,51074,55382,60032,

%U 64932,69927,75117,80672,86500,92446,98610,105162,112010,118999,126229,133870,141830

%N Number of (5+1) X (n+1) 0..1 arrays with every 2 X 2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically.

%H R. H. Hardin, <a href="/A258558/b258558.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + a(n-4) - 3*a(n-5) + 3*a(n-6) - a(n-7) for n>12.

%F Empirical g.f.: x*(480 - 111*x - 163*x^2 + 109*x^3 - 849*x^4 + 441*x^5 + 245*x^6 - 309*x^7 + 214*x^8 - 230*x^9 + 88*x^10 + 108*x^11) / ((1 - x)^4*(1 + x)*(1 + x^2)). - _Colin Barker_, Dec 22 2018

%e Some solutions for n=4:

%e ..1..0..0..0..0....1..0..0..1..1....0..0..0..1..1....0..1..1..1..1

%e ..0..0..0..0..0....1..0..0..0..0....0..0..0..0..0....0..0..0..0..0

%e ..1..1..0..0..1....1..0..0..0..1....1..0..0..0..1....1..1..1..1..1

%e ..1..0..0..1..1....0..0..0..0..1....0..0..0..1..1....0..0..0..0..0

%e ..1..1..1..1..1....1..1..0..0..1....1..1..1..1..1....1..1..1..1..1

%e ..1..1..0..0..1....1..0..0..0..1....0..0..0..0..1....1..1..0..0..0

%Y Row 5 of A258554.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jun 03 2015

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Last modified September 25 23:58 EDT 2021. Contains 347664 sequences. (Running on oeis4.)