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%I #6 Apr 27 2021 15:30:17
%S 0,304,27144,953236,31906806,977717308,28739292730,819460734096,
%T 22863636278820,627462391921784,16998237537647454,455708712521193672,
%U 12112703985140255876,319648041131418167054,8383975282118464984646
%N Number of 4 X n 0..2 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
%C Row 4 of A281326.
%H R. H. Hardin, <a href="/A281329/b281329.txt">Table of n, a(n) for n = 1..166</a>
%e Some solutions for n=3
%e ..0..1..0. .0..0..0. .0..0..1. .0..1..0. .0..1..1. .0..0..0. .0..1..1
%e ..0..1..2. .1..1..0. .1..2..1. .2..0..2. .2..2..0. .1..2..1. .0..0..0
%e ..2..2..1. .2..1..0. .1..1..2. .1..2..1. .0..0..0. .0..2..1. .0..2..0
%e ..1..2..1. .0..2..2. .1..2..0. .1..1..1. .2..2..1. .1..2..1. .1..2..0
%Y Cf. A281326.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 20 2017
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