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Number of (n+2)X7 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 16247580,40672735,43980907,69792825,207096000,1139760144,6656676736,

%T 61015724528,513802492708,3004591151584,27074363705888,

%U 227330083011172,1328325507137504,11969420064914272,100501902404767796

%N Number of (n+2)X7 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 5 of A204607

%H R. H. Hardin, <a href="/A204604/b204604.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>16

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 17 2012