A297459 - OEIS

%I #8 Feb 28 2019 16:43:54

%S 8,19,92,285,1143,3933,14817,52868,194822,704284,2575201,9352440,

%T 34103042,124055943,451921339,1644897204,5990104595,21807171062,

%U 79403933671,289093577711,1052597637063,3832392357045,13953632474038

%N Number of 3 X n 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0 or 2 neighboring 1s.

%H R. H. Hardin, <a href="/A297459/b297459.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) + 4*a(n-2) - 7*a(n-3) + 8*a(n-4) - 19*a(n-5) + 8*a(n-6) + 2*a(n-8).

%F Empirical g.f.: x*(8 - 5*x + 3*x^2 - 11*x^3 - 11*x^4 + 8*x^5 + 2*x^6 + 2*x^7) / (1 - 3*x - 4*x^2 + 7*x^3 - 8*x^4 + 19*x^5 - 8*x^6 - 2*x^8). - _Colin Barker_, Feb 28 2019

%e Some solutions for n=7:

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

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

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

%Y Row 3 of A297457.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 30 2017