A185764 - OEIS

%I #10 Apr 16 2018 18:03:08

%S 264,1128,5272,24832,118248,562800,2680000,12760448,60758008,

%T 289298976,1377475600,6558823720,31229466280,148698094888,

%U 708018868272,3371204831376,16051843045856,76430201410000,363919139999024

%N Number of (n+1) X 5 binary arrays with no 2 X 2 subblock trace equal to any horizontal or vertical neighbor 2 X 2 subblock trace.

%C Column 4 of A185769.

%H R. H. Hardin, <a href="/A185764/b185764.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = a(n-1) + 17*a(n-2) + 9*a(n-3) - 22*a(n-4) - a(n-5) + a(n-6) - 6*a(n-7) for n>9.

%F Empirical g.f.: 8*x*(33 + 108*x - 43*x^2 - 249*x^3 - 69*x^4 + 5*x^5 + 43*x^6 + 81*x^7 + 18*x^8) / (1 - x - 17*x^2 - 9*x^3 + 22*x^4 + x^5 - x^6 + 6*x^7). - _Colin Barker_, Apr 16 2018

%e Some solutions for 3 X 5:

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

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

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

%Y Cf. A185769.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 03 2011