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A231265 Number of (3+1)X(n+1) 0..2 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with values 0..2 introduced in row major order.

%I A231265 #6 Jul 23 2025 06:21:29
%S A231265 22,89,304,1253,5109,21894,94234,411978,1804685,7941968,34969518,
%T A231265 154177482,679856170,2999022193,13230140405,58371368067,257539346061,
%U A231265 1136325839478,5013778949950,22122400344087,97611358054570
%N A231265 Number of (3+1)X(n+1) 0..2 arrays with no element unequal to a strict majority of its horizontal and antidiagonal neighbors, with values 0..2 introduced in row major order.
%C A231265 Row 3 of A231263
%H A231265 R. H. Hardin, <a href="/A231265/b231265.txt">Table of n, a(n) for n = 1..210</a>
%F A231265 Empirical: a(n) = 9*a(n-1) -20*a(n-2) -36*a(n-3) +220*a(n-4) -282*a(n-5) -226*a(n-6) +1107*a(n-7) -1331*a(n-8) +254*a(n-9) +1022*a(n-10) -257*a(n-11) -2156*a(n-12) +2602*a(n-13) +2385*a(n-14) -8433*a(n-15) +7492*a(n-16) -959*a(n-17) -1626*a(n-18) -531*a(n-19) -3536*a(n-20) +3860*a(n-21) -2019*a(n-22) +4258*a(n-23) -1660*a(n-24) +328*a(n-25) -368*a(n-26) -96*a(n-27) for n>28
%e A231265 Some solutions for n=3
%e A231265 ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..1..1....0..0..1..1
%e A231265 ..1..1..1..1....1..1..0..0....0..0..0..0....0..1..1..1....0..1..0..0
%e A231265 ..2..2..2..2....1..0..0..0....0..0..0..1....1..2..2..2....1..0..0..2
%e A231265 ..2..2..2..2....2..2..2..2....0..0..1..1....2..2..2..2....2..2..2..2
%K A231265 nonn
%O A231265 1,1
%A A231265 _R. H. Hardin_, Nov 06 2013