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Number of nX2 0..2 arrays with every row and column running average nondecreasing rightwards and downwards but some diagonal running average having a decrease
1

%I #5 Mar 31 2012 12:36:43

%S 0,0,1,6,24,80,239,665,1756,4459,10978,26369,62066,143647,327756,

%T 738794,1647917,3642331,7986246,17387367,37618098,80932917,173248897,

%U 369190346,783527077,1656712522,3491205863,7334452733,15365201271,32106206735

%N Number of nX2 0..2 arrays with every row and column running average nondecreasing rightwards and downwards but some diagonal running average having a decrease

%C Column 2 of A201195

%H R. H. Hardin, <a href="/A201189/b201189.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 10*a(n-1) -37*a(n-2) +48*a(n-3) +55*a(n-4) -237*a(n-5) +186*a(n-6) +209*a(n-7) -450*a(n-8) +150*a(n-9) +280*a(n-10) -297*a(n-11) +20*a(n-12) +126*a(n-13) -69*a(n-14) -5*a(n-15) +16*a(n-16) -4*a(n-17)

%e Some solutions for n=9

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

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

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

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

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

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

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

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

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

%K nonn

%O 1,4

%A _R. H. Hardin_ Nov 28 2011