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A231413 Number of (n+1) X (1+1) 0..2 arrays with no element equal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order. 4

%I #8 Feb 21 2018 09:43:32

%S 9,50,285,1617,9188,52193,296511,1684466,9569425,54363701,308839124,

%T 1754508933,9967330587,56624207962,321681006005,1827463435305,

%U 10381783646596,58978707645369,335056872107879,1903451466275938

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

%C Column 1 of A231419.

%H R. H. Hardin, <a href="/A231413/b231413.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) - 11*a(n-3) + 4*a(n-4).

%F Empirical g.f.: x*(9 - 4*x - 15*x^2 + 6*x^3) / (1 - 6*x + 11*x^3 - 4*x^4). - _Colin Barker_, Feb 21 2018

%e Some solutions for n=5:

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

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

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

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

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

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

%Y Cf. A231419.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 08 2013

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Last modified May 23 13:40 EDT 2024. Contains 372763 sequences. (Running on oeis4.)