A208115 - OEIS

%I #8 Jun 28 2018 09:18:37

%S 15,225,825,3025,7315,17689,34713,68121,117711,203401,322465,511225,

%T 761475,1134225,1611345,2289169,3133423,4289041,5697321,7568001,

%U 9807315,12709225,16131625,20475625,25534575,31843449,39111633,48038761,58227331

%N Number of n X 5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.

%C Column 5 of A208118.

%H R. H. Hardin, <a href="/A208115/b208115.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) + 4*a(n-2) - 10*a(n-3) - 5*a(n-4) + 20*a(n-5) - 20*a(n-7) + 5*a(n-8) + 10*a(n-9) - 4*a(n-10) - 2*a(n-11) + a(n-12).

%F Empirical g.f.: x*(15 + 195*x + 315*x^2 + 625*x^3 + 290*x^4 + 34*x^5 - 50*x^6 + 14*x^7 + 7*x^8 - 5*x^9 - x^10 + x^11) / ((1 - x)^7*(1 + x)^5). - _Colin Barker_, Jun 28 2018

%e Some solutions for n=4:

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

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

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

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

%Y Cf. A208118.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 23 2012