A282831 - OEIS

A282831

Number of nX1 0..1 arrays with no 1 equal to more than one of its king-move neighbors, with the exception of exactly two elements.

%I #6 Feb 23 2017 04:29:50

%S 0,0,0,1,2,5,13,29,65,143,307,652,1369,2846,5870,12022,24470,49538,

%T 99802,200195,400004,796395,1580451,3127083,6170303,12144313,23846197,

%U 46721478,91354371,178285068,347316524,675472732,1311610492,2543054356,4923747716

%N Number of nX1 0..1 arrays with no 1 equal to more than one of its king-move neighbors, with the exception of exactly two elements.

%C Column 1 of A282838.

%H R. H. Hardin, <a href="/A282831/b282831.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) -2*a(n-3) -6*a(n-4) +4*a(n-6) +6*a(n-7) +3*a(n-8) +a(n-9).

%F Empirical: G.f.: x^4*(-1+x+x^2)/(x^3+x^2+x-1)^3 . - _R. J. Mathar_, Feb 23 2017

%e All solutions for n=6

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

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

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

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

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

%Y Cf. A282838.

%K nonn

%O 1,5

%A _R. H. Hardin_, Feb 22 2017