login
T(n,k) = number of (n+1) X (k+1) 0..3 arrays with no 2 X 2 subblock having the same number of clockwise edge increases as its horizontal neighbors or the same number of counterclockwise edge increases as its vertical neighbors.
7

%I #8 Dec 10 2015 02:00:54

%S 256,2120,2120,17920,25512,17920,151824,310912,310912,151824,1285076,

%T 3825072,5550256,3825072,1285076,10876432,47118720,101702648,

%U 101702648,47118720,10876432,92062852,583496376,1912957100,2938041784,1912957100

%N T(n,k) = number of (n+1) X (k+1) 0..3 arrays with no 2 X 2 subblock having the same number of clockwise edge increases as its horizontal neighbors or the same number of counterclockwise edge increases as its vertical neighbors.

%C Table starts

%C .......256........2120..........17920.........151824.........1285076

%C ......2120.......25512.........310912........3825072........47118720

%C .....17920......310912........5550256......101702648......1912957100

%C ....151824.....3825072......101702648.....2938041784.....90234357280

%C ...1285076....47118720.....1912957100....90234357280...4762415402596

%C ..10876432...583496376....36783376600..2915195222352.273204243466080

%C ..92062852..7243545064...718097911212.97376756715048

%C .779221408.90103381160.14168783055608

%H R. H. Hardin, <a href="/A205954/b205954.txt">Table of n, a(n) for n = 1..59</a>

%e Some solutions for n=4, k=3:

%e ..3..2..2..3....0..1..0..0....1..2..1..2....1..0..0..0....2..2..1..1

%e ..1..1..3..3....0..2..0..0....3..0..1..3....0..3..3..2....2..2..0..2

%e ..1..2..1..2....0..1..1..2....0..0..2..3....3..3..3..0....3..1..0..1

%e ..2..3..0..0....2..1..1..0....0..0..1..3....1..2..0..0....2..2..2..1

%e ..0..3..0..0....3..3..2..3....0..2..1..2....1..1..2..3....2..2..3..2

%Y Column 1 is A205459.

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_, Feb 02 2012