A301792 - OEIS

%I #4 Mar 26 2018 16:43:28

%S 4,13,12,17,25,38,59,93,148,237,381,614,991,1601,2588,4185,6769,10950,

%T 17715,28661,46372,75029,121397,196422,317815,514233,832044,1346273,

%U 2178313,3524582,5702891,9227469,14930356,24157821,39088173,63245990

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

%C Row 3 of A301790.

%H R. H. Hardin, <a href="/A301792/b301792.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) -a(n-3) for n>5

%e Some solutions for n=5

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

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

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

%Y Cf. A301790.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 26 2018