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1/16 the number of (n+1) X 5 0..7 arrays with every 2 X 2 subblock strictly increasing clockwise or counterclockwise with one decrease, and at least two adjacent blocks having the same increasing direction.
1

%I #7 Oct 06 2015 22:08:18

%S 9403,550268,32555965,3202350892,470757143497,85938883577009,

%T 16327766532728500,3094892136980310870,579019469263278106043,

%U 106955380615838654906545,19539849220501390068072761

%N 1/16 the number of (n+1) X 5 0..7 arrays with every 2 X 2 subblock strictly increasing clockwise or counterclockwise with one decrease, and at least two adjacent blocks having the same increasing direction.

%C Column 4 of A183738.

%H R. H. Hardin, <a href="/A183733/b183733.txt">Table of n, a(n) for n = 1..58</a>

%e Some solutions with the first block increasing clockwise for 3 X 5:

%e ..0..1..2..0..2....0..3..2..3..4....4..6..0..3..7....4..6..2..3..4

%e ..7..4..3..6..5....7..6..0..6..5....3..2..1..2..1....3..0..1..7..6

%e ..6..5..1..0..2....3..5..2..3..4....4..5..7..4..5....4..6..2..3..5

%e ...

%e ...R..R..L..R.......R..L..R..R.......R..R..L..R.......R..L..R..R...

%e ...R..L..R..L.......L..R..L..L.......L..L..R..L.......L..R..L..L...

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 06 2011