login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A116903 Seaweeds(n): number of n-step self-avoiding walks on upper two quadrants grid starting at origin. 2
1, 3, 7, 19, 49, 131, 339, 899, 2345, 6199, 16225, 42811, 112285, 296051, 777411, 2049025, 5384855, 14190509, 37313977, 98324565, 258654441, 681552747, 1793492411 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

These walks remind me of fluctuant seaweeds anchored to the sea bottom.

LINKS

Table of n, a(n) for n=0..22.

M. N. Barber et al., Some tests of scaling theory for a self-avoiding walk attached to a surface [From Vladeta Jovovic, Nov 26 2008]

EXAMPLE

The 19 seaweeds of length 3. X marks the origin = anchor point.

........................................................

O-O-O...O-O.. .O-O...O-O....O..O-O-O...O......O..O-O....

....|.....|.. .|.....|......|..|.......|......|....|....

....X...X-O....O.....O-X....O..X..O-O..O-O....O....O-X..

...............|............|.......|....|....|.........

O-O.....O-O....X....O.......O..O....O....X..X-O.......O.

|.|.....|...........|.......|..|....|.................|.

X.O...X-O.....O-O...O-O-X...X..O....X.....O.........O-O.

..............|.|..............|..........|.........|...

..X-O-O-O.....O.X...O-O-O-X....O-X....X-O-O.........X...

........................................................

CROSSREFS

Cf. A001411, A038373, A116903.

Sequence in context: A061646 A017926 A017927 * A298416 A151266 A147234

Adjacent sequences:  A116900 A116901 A116902 * A116904 A116905 A116906

KEYWORD

nonn

AUTHOR

Giovanni Resta, Feb 15 2006

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 20 20:40 EST 2019. Contains 329347 sequences. (Running on oeis4.)