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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 (list; table; graph; refs; listen; history; text; internal format)
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

R. H. Hardin, Table of n, a(n) for n = 1..684

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

Adjacent sequences:  A186485 A186486 A186487 * A186489 A186490 A186491

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Feb 22 2011

STATUS

approved

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Last modified August 8 13:57 EDT 2020. Contains 336298 sequences. (Running on oeis4.)