A183577 - OEIS

%I #5 Mar 31 2012 12:35:52

%S 2,14,78,407,2216,12024,65277,354615,1926386,10465655,56858572,

%T 308906899,1678265791,9117888439,49536803509,269129777690,

%U 1462162196206,7943819360442,43158185018445,234475238671702,1273886693818638

%N Half the number of nX2 0..3 arrays with each element equal to either the maximum or the minimum of its horizontal and vertical neighbors

%C Column 2 of A183584

%H R. H. Hardin, <a href="/A183577/b183577.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n)=7*a(n-1)-8*a(n-2)+4*a(n-3)-41*a(n-4)+20*a(n-5)-13*a(n-6)+130*a(n-7)+32*a(n-8)+94*a(n-9)-118*a(n-10)-88*a(n-11)-93*a(n-12)-a(n-13)+20*a(n-14)

%e Some solutions with a(1,1)<=1 for 3X2

%e ..0..0....1..3....1..1....0..2....0..0....1..1....1..0....0..0....1..1....0..0

%e ..0..0....1..3....2..1....0..2....3..0....2..0....1..0....0..0....0..0....2..2

%e ..0..0....1..1....2..2....0..2....3..0....2..0....1..0....1..1....2..2....0..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 05 2011