A196863 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 3,4,2,0,1 for x=0,1,2,3,4

1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 4, 7, 4, 1, 1, 6, 12, 12, 6, 1, 1, 9, 26, 35, 26, 9, 1, 1, 13, 56, 102, 102, 56, 13, 1, 1, 19, 113, 281, 473, 281, 113, 19, 1, 1, 28, 235, 787, 1900, 1900, 787, 235, 28, 1, 1, 41, 490, 2237, 7428, 11280, 7428, 2237, 490, 41, 1, 1, 60, 1012, 6346

Offset

1,5

Comments

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

.1..2....3.....4......6........9........13.........19...........28

.1..3....7....12.....26.......56.......113........235..........490

.1..4...12....35....102......281.......787.......2237.........6346

.1..6...26...102....473.....1900......7428......29859.......120761

.1..9...56...281...1900....11280.....62298.....350779......1995082

.1.13..113...787...7428....62298....494579....3938849.....31419870

.1.19..235..2237..29859...350779...3938849...44461736....500005832

.1.28..490..6346.120761..1995082..31419870..500005832...7927841482

.1.41.1012.17976.488123.11350977.250968250.5615771466.125246087887

Links

R. H. Hardin, Table of n, a(n) for n = 1..264

Example

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

Crossrefs

Column 2 is A000930(n+1)

Sequence in context: A104881 A171699 A104878 * A196922 A135597 A169945

Adjacent sequences: A196860 A196861 A196862 * A196864 A196865 A196866

Keyword

nonn,tabl

Author

R. H. Hardin Oct 06 2011

Status

approved