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Number of (2+2)X(n+2) 0..2 arrays with no increasing sequence of length 3 horizontally or diagonally downwards
1

%I #5 Aug 11 2014 22:45:56

%S 430608,27826929,1777375908,113340508656,7222554443566,

%T 460194589763836,29320690351065445,1868112829445921314,

%U 119023011702892254856,7583305026602442683556,483154524353295641124009

%N Number of (2+2)X(n+2) 0..2 arrays with no increasing sequence of length 3 horizontally or diagonally downwards

%C Row 2 of A233618

%H R. H. Hardin, <a href="/A233620/b233620.txt">Table of n, a(n) for n = 1..210</a>

%H R. H. Hardin, <a href="/A233620/a233620.txt">Empirical recurrence of order 68</a>

%F Empirical recurrence of order 68 (see link above)

%e Some solutions for n=1

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 14 2013