A300541 - OEIS

%I #4 Mar 08 2018 12:31:25

%S 1,11,71,450,2879,18365,117146,747252,4766519,30404411,193941921,

%T 1237105726,7891179813,50335810076,321079209472,2048081844697,

%U 13064188271417,83333102938721,531560469056352,3390687761515265

%N Number of nX3 0..1 arrays with every element equal to 1, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

%C Column 3 of A300546.

%H R. H. Hardin, <a href="/A300541/b300541.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) +9*a(n-2) -8*a(n-4) -3*a(n-5) +4*a(n-6) +4*a(n-7) +2*a(n-8) for n>10

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A300546.

%K nonn

%O 1,2

%A _R. H. Hardin_, Mar 08 2018