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%I #6 Apr 05 2020 22:55:28
%S 4,13,49,373,2259,18114,120058,959041,6725380,53524100,389145239,
%T 3078502323,22909373317,180462930528,1364622501692,10722180215723,
%U 81993405397067,643447267719348,4960055945696896,38910411283028492
%N Number of 3 X n 0..1 arrays with the number of 1's horizontally, diagonally or antidiagonally adjacent to some 0 equal to the number of 0's adjacent to some 1, with top left element zero.
%C Row 3 of A284334.
%H R. H. Hardin, <a href="/A284336/b284336.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4
%e ..0..1..1..1. .0..0..0..0. .0..0..0..1. .0..1..1..0. .0..0..1..1
%e ..1..1..0..0. .0..0..0..0. .0..1..1..1. .0..1..0..1. .1..1..0..0
%e ..0..0..1..0. .0..0..0..0. .1..0..0..1. .1..0..1..0. .1..1..0..0
%Y Cf. A284334.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 25 2017