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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A240630 Number of n X n 0..1 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..1 introduced in row major order 0
1, 8, 129, 4989, 470170, 109584463, 63213422873, 90394294712339, 320691260884992280, 2823496298905253740496 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Diagonal of A240636

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

Some solutions for n=4

..0..1..0..0....0..1..1..1....0..1..0..1....0..0..1..1....0..1..0..1

..0..1..0..1....1..1..0..0....0..1..0..0....1..1..0..1....0..0..0..0

..0..1..1..0....0..0..1..1....1..0..1..1....0..0..0..0....1..1..0..0

..1..0..1..1....1..0..1..1....1..1..1..0....1..1..0..0....0..1..1..1

CROSSREFS

Sequence in context: A073701 A239756 A295240 * A187609 A241076 A222429

Adjacent sequences:  A240627 A240628 A240629 * A240631 A240632 A240633

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 09 2014

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 December 5 23:36 EST 2019. Contains 329784 sequences. (Running on oeis4.)