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Number of (n+2)X9 0..2 arrays with every 3X3 subblock having three strictly increasing elements in a row horizontally, vertically or nw-to-se diagonally exactly one way
1

%I #5 Mar 31 2012 12:37:02

%S 1240455298,1982068849,2572437376,4518555426,6656676736,9620299328,

%T 20253298532,128896188864,1430854315232,8336227917170,59924952387184,

%U 645348966859136,3709285229683898,26509588554453184,285311677590771520

%N Number of (n+2)X9 0..2 arrays with every 3X3 subblock having three strictly increasing elements in a row horizontally, vertically or nw-to-se diagonally exactly one way

%C Column 7 of A204607

%H R. H. Hardin, <a href="/A204606/b204606.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 442*a(n-3) +43*a(n-6) for n>18

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 17 2012