A202906 T(n,k) = Number of n X k 0..1 arrays with every one equal to some NW, E or S neighbor.

1, 1, 1, 1, 4, 1, 1, 14, 14, 1, 1, 40, 93, 40, 1, 1, 116, 494, 494, 116, 1, 1, 344, 2801, 4892, 2801, 344, 1, 1, 1016, 16062, 51068, 51068, 16062, 1016, 1, 1, 2992, 91161, 538672, 993219, 538672, 91161, 2992, 1, 1, 8816, 517646, 5654616, 19675348, 19675348

Offset

1,5

Links

R. H. Hardin, Table of n, a(n) for n = 1..419

Example

Table starts
.1....1......1........1..........1.............1...............1
.1....4.....14.......40........116...........344............1016
.1...14.....93......494.......2801.........16062...........91161
.1...40....494.....4892......51068........538672.........5654616
.1..116...2801....51068.....993219......19675348.......387217701
.1..344..16062...538672...19675348.....734614472.....27173404568
.1.1016..91161..5654616..387217701...27173404568...1886797510045
.1.2992.517646.59369072.7615580812.1004314801728.130876616267032
Some solutions for n=5 k=3
..1..1..1....1..1..0....1..1..0....0..0..0....0..1..1....0..1..1....0..0..1
..1..0..1....0..1..1....0..1..0....0..1..1....1..1..1....1..1..1....1..0..1
..1..1..0....0..0..0....1..1..0....1..1..1....0..1..0....1..1..1....1..1..1
..1..1..1....0..0..0....1..1..1....1..1..0....1..1..1....1..1..1....1..1..1
..1..1..0....0..0..0....0..0..1....0..0..1....0..0..0....0..0..1....0..1..0

Crossrefs

Sequence in context: A050154 A179454 A058711 * A177984 A157013 A346876

Adjacent sequences: A202903 A202904 A202905 * A202907 A202908 A202909

Keyword

nonn,tabl

Author

R. H. Hardin, Dec 25 2011

Status

approved