A183362 T(n,k)=One quarter the number of nXk 1..4 arrays with no two neighbors of any element equal to each other

1, 4, 4, 12, 36, 12, 36, 144, 144, 36, 108, 576, 432, 576, 108, 324, 2304, 1296, 1296, 2304, 324, 972, 9216, 3888, 3600, 3888, 9216, 972, 2916, 36864, 11664, 9216, 9216, 11664, 36864, 2916, 8748, 147456, 34992, 24336, 24192, 24336, 34992, 147456, 8748

Offset

1,2

Comments

Table starts

.....1.......4.....12......36.....108.....324.....972.....2916.....8748

.....4......36....144.....576....2304....9216...36864...147456...589824

....12.....144....432....1296....3888...11664...34992...104976...314928

....36.....576...1296....3600....9216...24336...63504...166464...435600

...108....2304...3888....9216...24192...57600..137088...331776...802944

...324....9216..11664...24336...57600..147456..331776...746496..1679616

...972...36864..34992...63504..137088..331776..829440..1806336..3852288

..2916..147456.104976..166464..331776..746496.1806336..4460544..9437184

..8748..589824.314928..435600..802944.1679616.3852288..9437184.23003136

.26244.2359296.944784.1140624.1937664.3873024.8294400.19501056.47775744

Links

R. H. Hardin, Table of n, a(n) for n = 1..335

Example

Some solutions for 6X5 with a(1,1)=1
..1..1..3..2..2....1..1..3..2..1....1..1..4..2..3....1..1..3..2..4
..4..4..3..1..1....2..2..4..4..3....3..3..4..1..3....4..4..3..1..1
..3..2..2..4..4....4..3..1..1..3....4..2..2..1..4....3..2..2..4..3
..3..1..1..3..2....4..3..2..2..4....4..1..3..3..4....3..1..1..4..3
..2..4..4..3..1....1..1..4..3..1....3..1..4..2..2....2..4..3..2..2
..1..3..2..2..1....2..2..4..3..1....3..2..4..1..3....1..4..3..1..4

Crossrefs

Column 1 is A003946(n-1)

Sequence in context: A359709 A228612 A038804 * A353615 A088838 A367688

Adjacent sequences: A183359 A183360 A183361 * A183363 A183364 A183365

Keyword

nonn,tabl

Author

R. H. Hardin Jan 04 2011

Status

approved