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%I #8 May 02 2024 09:49:06
%S 0,3,27,254,2301,19053,149696,1124969,8178511,57898166,401186545,
%T 2731110793,18318459744,121328163101,794920836163,5159325575790,
%U 33210311871861,212217346520565,1347303236328128,8503951716838241
%N Number of 2 X n 0..2 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
%C Row 2 of A279657.
%H R. H. Hardin, <a href="/A279658/b279658.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 17*a(n-1) -90*a(n-2) +75*a(n-3) +591*a(n-4) -924*a(n-5) -1263*a(n-6) +2511*a(n-7) +810*a(n-8) -2675*a(n-9) +409*a(n-10) +924*a(n-11) -464*a(n-12) +64*a(n-13).
%e Some solutions for n=4:
%e ..0..1..2..0. .0..1..1..0. .0..0..1..0. .0..1..1..1. .0..1..1..0
%e ..2..2..1..1. .1..0..0..2. .0..2..2..0. .0..2..0..0. .1..0..0..1
%Y Cf. A279657.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 16 2016