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%I #6 Apr 05 2020 23:45:25
%S 0,9,48,554,3334,30837,202363,1733660,12139768,99907487,729039938,
%T 5866737162,43944684689,349284676982,2660349798813,21006556689388,
%U 161738436141669,1272996087653588,9871903975910464,77596716393162478
%N Number of n X 3 0..1 arrays with the number of 1's horizontally, diagonally or antidiagonally adjacent to some 0 two less than the number of 0's adjacent to some 1.
%C Column 3 of A293100.
%H R. H. Hardin, <a href="/A293095/b293095.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..0..1. .0..0..1. .0..1..1. .1..1..0. .0..0..0. .1..0..0. .0..0..0
%e ..0..1..0. .1..1..0. .0..1..0. .1..0..0. .0..1..1. .0..1..0. .1..0..0
%e ..0..0..0. .0..0..0. .1..1..0. .0..1..0. .1..1..0. .0..0..1. .1..1..0
%e ..1..1..1. .1..1..0. .0..1..0. .0..1..0. .1..0..0. .1..1..0. .0..1..0
%Y Cf. A293100.
%K nonn
%O 1,2
%A _R. H. Hardin_, Sep 30 2017