A258557 - OEIS

%I #8 Dec 22 2018 11:33:54

%S 228,652,1244,1891,2509,3314,4313,5356,6331,7470,8820,10231,11591,

%T 13132,14901,16748,18561,20572,22828,25179,27513,30062,32873,35796,

%U 38719,41874,45308,48871,52451,56280,60405,64676,68981,73552,78436,83483,88581,93962

%N Number of (4+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="/A258557/b258557.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>11.

%F Empirical g.f.: x*(228 - 32*x - 28*x^2 - 113*x^3 - 312*x^4 + 248*x^5 + 35*x^6 - 37*x^7 - 28*x^8 + 16*x^9 + 40*x^10) / ((1 - x)^4*(1 + x)*(1 + x^2)). - _Colin Barker_, Dec 22 2018

%e Some solutions for n=4:

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

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

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

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

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

%Y Row 4 of A258554.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jun 03 2015