A260008 - OEIS

%I #8 Dec 27 2018 14:56:06

%S 36,49,109,209,436,828,1744,3344,7005,13424,28067,53992,112602,216997,

%T 451535,872258,1811173,3505729,7264641,14089470,29141208,56621872,

%U 116900698,227536583,468975418,914316503,1881490568,3673849908

%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000101 00010101 or 01010101.

%H R. H. Hardin, <a href="/A260008/b260008.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-2) + 7*a(n-4) + a(n-5) + 2*a(n-6) + a(n-7) - a(n-8) + a(n-9) for n>10.

%F Empirical g.f.: x*(36 + 49*x + 37*x^2 + 111*x^3 - 34*x^4 + 31*x^5 - 12*x^6 - 18*x^7 + 25*x^8 - 10*x^9) / (1 - 2*x^2 - 7*x^4 - x^5 - 2*x^6 - x^7 + x^8 - x^9). - _Colin Barker_, Dec 27 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 1 of A260015.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 13 2015