login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A146721 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1100-1111-1000 pattern in any orientation. 0
1, 1, 1, 1, 5, 21, 49, 265, 1337, 7025, 55305, 543439, 6271235, 94294061, 1709408045, 38060613237 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..16.

EXAMPLE

Maximal 8 X 8 example

.0.1.1.1.0.1.1.1

.0.1.1.0.0.0.1.1

.0.0.1.0.0.0.1.0

.0.0.1.0.0.0.1.0

.0.1.0.0.0.1.0.0

.0.1.0.0.0.1.0.0

.1.1.0.0.0.1.1.0

.1.1.1.0.1.1.1.0

CROSSREFS

Sequence in context: A041825 A022268 A201279 * A099979 A039659 A147238

Adjacent sequences:  A146718 A146719 A146720 * A146722 A146723 A146724

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 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 24 10:33 EST 2020. Contains 331193 sequences. (Running on oeis4.)