login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A211050 1/3 the number of n X n 0..2 symmetric matrices with every element equal to two or three horizontal and vertical neighbors 0
0, 1, 1, 11, 69, 1059, 21565, 767763, 42018069, 3765457981, 536609175439, 123351155903565, 45453341030199701, 26933811670713434089 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,4
LINKS
EXAMPLE
Some solutions for n=4
..0..0..0..0....2..2..0..0....2..2..2..2....0..0..1..1....0..0..0..0
..0..0..0..0....2..2..0..0....2..1..1..2....0..0..1..1....0..0..0..0
..0..0..2..2....0..0..0..0....2..1..1..2....1..1..1..1....0..0..1..1
..0..0..2..2....0..0..0..0....2..2..2..2....1..1..1..1....0..0..1..1
CROSSREFS
Sequence in context: A182188 A099336 A236320 * A295074 A173200 A071746
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 30 2012
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 21 21:50 EDT 2024. Contains 373559 sequences. (Running on oeis4.)