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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
1

%I #4 Nov 06 2013 07:59:22

%S 22,89,304,1253,5109,21894,94234,411978,1804685,7941968,34969518,

%T 154177482,679856170,2999022193,13230140405,58371368067,257539346061,

%U 1136325839478,5013778949950,22122400344087,97611358054570

%N 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 Row 3 of A231263

%H R. H. Hardin, <a href="/A231265/b231265.txt">Table of n, a(n) for n = 1..210</a>

%F 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 Some solutions for n=3

%e ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..1..1....0..0..1..1

%e ..1..1..1..1....1..1..0..0....0..0..0..0....0..1..1..1....0..1..0..0

%e ..2..2..2..2....1..0..0..0....0..0..0..1....1..2..2..2....1..0..0..2

%e ..2..2..2..2....2..2..2..2....0..0..1..1....2..2..2..2....2..2..2..2

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 06 2013