%I #6 Apr 05 2020 22:32:56
%S 3,13,62,461,2872,21790,154108,1174235,8682209,66280564,500956582,
%T 3842195970,29399659661,226595079490,1747037865422,13523344571285,
%U 104799855374221,814166845363267,6333123661559589,49348005883512820
%N Number of n X 3 0..1 arrays with the number of 1's horizontally or vertically adjacent to some 0 equal to the number of 0's adjacent to some 1, with top left element zero.
%C Column 3 of A284165.
%H R. H. Hardin, <a href="/A284160/b284160.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..0..0. .0..1..1. .0..1..1. .0..0..1. .0..0..1. .0..0..1. .0..0..1
%e ..1..0..0. .1..1..1. .1..0..1. .1..1..1. .1..0..0. .1..0..0. .0..1..1
%e ..0..1..1. .0..1..0. .0..1..0. .1..0..0. .1..1..1. .0..1..1. .0..0..1
%e ..1..1..1. .0..1..0. .0..0..1. .0..1..0. .0..1..0. .1..0..1. .1..0..1
%Y Cf. A284165.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 21 2017