A260494 - OEIS

%I #8 Dec 29 2018 07:08:07

%S 48,83,218,464,722,1600,3446,6277,12596,26271,51082,100763,204716,

%T 406841,804806,1614143,3223294,6404160,12784652,25529935,50847034,

%U 101384899,202319592,403339059,804133704,1603982398,3198547326,6377529472

%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00001011.

%H R. H. Hardin, <a href="/A260494/b260494.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-3) + 4*a(n-4) + 4*a(n-5) + 4*a(n-6) + 4*a(n-7) + 3*a(n-8) + 2*a(n-9) + 3*a(n-10) + 2*a(n-11) + a(n-12) for n>14.

%F Empirical g.f.: x*(48 + 83*x + 218*x^2 + 272*x^3 + 198*x^4 + 204*x^5 + 194*x^6 + 137*x^7 + 104*x^8 + 126*x^9 + 82*x^10 + 26*x^11 - 6*x^12 - 2*x^13) / (1 - 4*x^3 - 4*x^4 - 4*x^5 - 4*x^6 - 4*x^7 - 3*x^8 - 2*x^9 - 3*x^10 - 2*x^11 - x^12). - _Colin Barker_, Dec 29 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 1 of A260501.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 27 2015