%I #4 Nov 26 2014 09:55:34

%S 81,484,2704,13456,64009,290521,1283689,5541316,23541904,98724096,

%T 410022001,1689785449,6922406401,28223328004,114636416400,

%U 464224195600,1875379608025,7561592527225,30441493099161,122399217842724

%N Number of (n+1)X(1+1) 0..2 arrays with nondecreasing maximum of every two consecutive values in every row and column

%C Column 1 of A250620

%H R. H. Hardin, <a href="/A250613/b250613.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 9*a(n-1) -15*a(n-2) -70*a(n-3) +208*a(n-4) +148*a(n-5) -795*a(n-6) +15*a(n-7) +1267*a(n-8) -318*a(n-9) -840*a(n-10) +280*a(n-11) +176*a(n-12) -64*a(n-13)

%e Some solutions for n=5

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 26 2014