%I #6 Apr 05 2020 22:43:28
%S 6,44,499,6511,91260,1317770,19371893,288303232,4330336770,
%T 65507133232,996599090507,15232184395483,233708530421124,
%U 3597476814925298,55530194727444557,859222993580853779,13322830756899018309
%N Number of n X 4 0..1 arrays with the number of 1's horizontally or antidiagonally adjacent to some 0 equal to the number of 0's adjacent to some 1, with top left element zero.
%C Column 4 of A284222.
%H R. H. Hardin, <a href="/A284218/b284218.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..0..0..1. .0..1..1..0. .0..1..0..0. .0..0..1..0. .0..0..1..1
%e ..0..1..1..0. .1..1..0..0. .1..1..1..1. .0..0..0..1. .0..0..1..0
%e ..1..1..1..1. .0..1..1..0. .0..0..0..1. .1..1..0..1. .0..1..1..0
%e ..0..0..0..0. .0..1..1..1. .1..0..1..1. .0..1..0..1. .1..1..1..1
%Y Cf. A284222.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 23 2017