A197090 T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,3,2,0,1 for x=0,1,2,3,4

1, 1, 1, 1, 2, 1, 1, 5, 5, 1, 1, 10, 25, 10, 1, 1, 26, 96, 96, 26, 1, 1, 65, 422, 631, 422, 65, 1, 1, 161, 1780, 5101, 5101, 1780, 161, 1, 1, 403, 7537, 37952, 71867, 37952, 7537, 403, 1, 1, 1006, 31911, 289564, 939690, 939690, 289564, 31911, 1006, 1, 1, 2511, 135283

Offset

1,5

Comments

Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 2's, every 3 is next to 3 0's, every 4 is next to 4 1's

Table starts

.1....1......1.........1...........1.............1................1

.1....2......5........10..........26............65..............161

.1....5.....25........96.........422..........1780.............7537

.1...10.....96.......631........5101.........37952...........289564

.1...26....422......5101.......71867........939690.........12635748

.1...65...1780.....37952......939690......21996614........522569033

.1..161...7537....289564....12635748.....522569033......21989908007

.1..403..31911...2200339...168802858...12390326286.....923559415946

.1.1006.135283..16713718..2257145231..293837693200...38737498552503

.1.2511.573054.127074214.30181119596.6966924806564.1625808615727565

Links

R. H. Hardin, Table of n, a(n) for n = 1..180

Example

Some solutions for n=6 k=4
..0..0..3..0....0..3..0..0....0..0..2..2....0..3..0..0....0..0..3..0
..0..3..0..0....0..0..0..3....0..0..2..2....0..0..0..3....0..0..0..0
..2..2..0..3....2..2..3..0....0..0..0..0....3..0..0..0....0..0..0..0
..2..2..0..0....2..2..0..0....0..0..0..0....0..0..3..0....2..2..0..0
..0..3..0..3....0..3..0..0....3..0..3..1....0..2..2..0....2..2..3..0
..0..0..0..0....0..0..3..0....0..0..0..0....0..2..2..0....0..0..0..0

Crossrefs

Column 2 is A196630

Sequence in context: A128564 A196636 A196641 * A008518 A264862 A176420

Adjacent sequences: A197087 A197088 A197089 * A197091 A197092 A197093

Keyword

nonn,tabl

Author

R. H. Hardin Oct 10 2011

Status

approved