A250794 - OEIS

%I #7 Nov 20 2018 09:54:45

%S 252,838,2776,9258,31220,105954,361344,1236058,4237556,14549610,

%T 50012080,172050098,592248148,2039649282,7026884288,24215293674,

%U 83465955764,287740551770,992085339216,3420905014178,11796889975188,40683768017330

%N Number of (n+1) X (5+1) 0..1 arrays with nondecreasing min(x(i,j),x(i,j-1)) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction.

%H R. H. Hardin, <a href="/A250794/b250794.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 10*a(n-1) - 33*a(n-2) + 24*a(n-3) + 79*a(n-4) - 138*a(n-5) - 3*a(n-6) + 100*a(n-7) - 18*a(n-8) - 20*a(n-9).

%F Empirical g.f.: 2*x*(126 - 841*x + 1356*x^2 + 1552*x^3 - 4886*x^4 + 609*x^5 + 3484*x^6 - 580*x^7 - 640*x^8) / ((1 - x)^2*(1 - 2*x)*(1 - 2*x - x^2)*(1 - 2*x - 2*x^2)*(1 - 2*x - 5*x^2)). - _Colin Barker_, Nov 20 2018

%e Some solutions for n=4:

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

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

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

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

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

%Y Column 5 of A250797.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 27 2014