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!)
A143874 Number of ways of placing kings with no more than 1 mutual attack on an n X n chessboard symmetric under 180 degree rotation. 1
1, 2, 3, 7, 18, 111, 497, 4630, 38327, 702227, 10398834 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..10.

CROSSREFS

Sequence in context: A160181 A096203 A328430 * A073641 A273006 A117763

Adjacent sequences:  A143871 A143872 A143873 * A143875 A143876 A143877

KEYWORD

nonn,more,hard

AUTHOR

R. H. Hardin, Sep 04 2008

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 January 26 23:54 EST 2022. Contains 350601 sequences. (Running on oeis4.)