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

%I #6 Mar 02 2023 14:19:04

%S 24,432,9600,192192,3917184,79306752,1607468544,32569451520,

%T 659942375424,13371898245120,270945239064576,5489964932136960,

%U 111239155883802624,2253957795356147712,45670301427851329536,925383976903713226752

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

%C Column 2 of A231324.

%H R. H. Hardin, <a href="/A231318/b231318.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 22*a(n-1) -776*a(n-3) +944*a(n-4) +7168*a(n-5) -12416*a(n-6) +9216*a(n-8) -4096*a(n-9).

%e Some solutions for n=4

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

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

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

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

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

%Y Cf. A231324.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 07 2013