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A186488
T(n,k)=Number of (n+1)X(k+1) 0..6 arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors
2
2401, 1169, 1169, 17119, 2923, 17119, 13411, 5947, 5947, 13411, 125368, 26982, 122034, 26982, 125368, 110155, 48875, 75899, 75899, 48875, 110155, 878507, 181792, 877068, 464292, 877068, 181792, 878507, 868467, 349085, 617557, 696553, 696553
OFFSET
1,1
COMMENTS
Table starts
....2401....1169....17119.....13411....125368.....110155.....878507.....868467
....1169....2923.....5947.....26982.....48875.....181792.....349085....1308972
...17119....5947...122034.....75899....877068.....617557....6170249....5056121
...13411...26982....75899....464292....696553....3225157....4596421...23135705
..125368...48875...877068....696553...7513081....4754437...52753837...38012473
..110155..181792...617557...3225157...4754437...24490909...30473221..176097889
..878507..349085..6170249...4596421..52753837...30473221..378414577..236000977
..868467.1308972..5056121..23135705..38012473..176097889..236000977.1358113549
.6231024.2606517.43638003..35032589.372605789..228669373.2684581153.1653455365
.6832034.9456818.40663383.165747519.310706825.1253936945.1947271657.9747375325
LINKS
FORMULA
Empirical, for every column: a(n)=2*a(n-1)+5*a(n-2)-12*a(n-3)+12*a(n-4)-6*a(n-5) for n>k+13
EXAMPLE
Some solutions for 4X3
..4..0..0....2..0..5....3..0..0....2..3..0....6..1..0....0..5..4....0..0..3
..3..0..0....0..2..0....2..0..0....4..0..3....2..0..1....0..0..5....0..0..0
..0..3..0....5..0..2....0..2..0....0..4..0....0..2..0....0..0..0....1..0..0
..3..0..3....0..5..1....4..0..2....6..0..4....6..0..2....0..0..0....6..1..0
CROSSREFS
Sequence in context: A005073 A176767 A018865 * A186487 A043396 A103125
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Feb 22 2011
STATUS
approved