A188988 - OEIS

%I #8 May 01 2018 09:39:01

%S 20,400,5304,68064,852448,10682432,133744640,1674569728,20965958400,

%T 262498839552,3286544012800,41148269700608,515185556441600,

%U 6450238643180032,80758433426035200,1011113686205526528

%N Number of n X 5 binary arrays without the pattern 0 0 1 antidiagonally or horizontally.

%C Column 5 of A188992.

%H R. H. Hardin, <a href="/A188988/b188988.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 13*a(n-1) +4*a(n-2) -132*a(n-3) +60*a(n-4) +320*a(n-5) -240*a(n-6) for n>8.

%F Empirical g.f.: 4*x*(5 + 35*x + 6*x^2 + 38*x^3 - 500*x^4 - 480*x^5 + 1560*x^6 - 576*x^7) / ((1 - 2*x)*(1 + 2*x)*(1 - 13*x + 80*x^3 - 60*x^4)). - _Colin Barker_, May 01 2018

%e Some solutions for 3 X 5:

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

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

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

%Y Cf. A188992.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 15 2011