A318077 - OEIS

%I #4 Aug 15 2018 13:24:57

%S 3,4,5,11,18,32,54,98,173,315,559,1008,1813,3290,5928,10716,19352,

%T 35036,63355,114651,207352,375184,678789,1228507,2222990,4022469,

%U 7278193,13171060,23835243,43132890,78050078,141238045,255588327,462524188

%N Number of nX3 0..1 arrays with every element unequal to 0, 1, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

%C Column 3 of A318082.

%H R. H. Hardin, <a href="/A318077/b318077.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +8*a(n-4) -2*a(n-5) -24*a(n-8) -3*a(n-9) +34*a(n-12) +4*a(n-13) -24*a(n-16) -a(n-17) +8*a(n-20) -a(n-24)

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A318082.

%K nonn

%O 1,1

%A _R. H. Hardin_, Aug 15 2018