A198604 T(n,k)=Number of 2nX2k 0..3 arrays with values 0..3 introduced in row major order and each element equal to exactly two horizontal and vertical neighbors

1, 1, 1, 2, 5, 2, 5, 32, 32, 5, 14, 251, 674, 251, 14, 41, 1985, 14396, 14396, 1985, 41, 122, 15761, 309770, 844228, 309770, 15761, 122, 365, 125168, 6671450, 49726877, 49726877, 6671450, 125168, 365, 1094, 994127, 143724590, 2934981667, 8055413256

Offset

1,4

Comments

Table starts

....1.......1..........2............5............14............41

....1.......5.........32..........251..........1985.........15761

....2......32........674........14396........309770.......6671450

....5.....251......14396.......844228......49726877....2934981667

...14....1985.....309770.....49726877....8055413256.1308245895665

...41...15761....6671450...2934981667.1308245895665

..122..125168..143724590.173328303620

..365..994127.3096625676

.1094.7895777

.3281

Links

R. H. Hardin, Table of n, a(n) for n = 1..60

Example

All solutions for n=2 k=2
..0..0..1..1....0..0..1..1....0..0..1..1....0..0..1..1....0..0..0..0
..0..0..1..1....0..0..1..1....0..0..1..1....0..0..1..1....0..1..1..0
..2..2..3..3....1..1..0..0....2..2..0..0....1..1..2..2....0..1..1..0
..2..2..3..3....1..1..0..0....2..2..0..0....1..1..2..2....0..0..0..0

Crossrefs

Column 1 is A007051(n-2)

Sequence in context: A240706 A240642 A240774 * A198253 A159989 A195702

Adjacent sequences: A198601 A198602 A198603 * A198605 A198606 A198607

Keyword

nonn,tabl

Author

R. H. Hardin Oct 27 2011

Status

approved