A202594 - OEIS

%I #8 Jun 01 2018 10:32:01

%S 126,510,1968,7722,30114,117708,459690,1795842,7014816,27402198,

%T 107040102,418129380,1633329054,6380241774,24923005584,97356232314,

%U 380300658210,1485560712012,5803015490538,22668201049266,88548331298112

%N Number of (n+2) X 3 binary arrays avoiding patterns 001 and 000 in rows and columns.

%C Column 1 of A202601.

%H R. H. Hardin, <a href="/A202594/b202594.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +7*a(n-2) +2*a(n-3) -a(n-4).

%F Empirical g.f.: 6*x*(21 + 43*x + 11*x^2 - 6*x^3) / (1 - 2*x - 7*x^2 - 2*x^3 + x^4). - _Colin Barker_, Jun 01 2018

%e Some solutions for n=3:

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

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

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

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

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

%Y Cf. A202601.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 21 2011