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!)
A146231 Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 1100-1111 pattern in any orientation. 0
1, 1, 1, 5, 17, 35, 163, 959, 6943, 61513, 740733, 9820359, 193942865, 4360418313, 137513801459 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Maximal 8 X 8 example

.1.1.0.0.1.1.1.1

.1.1.1.1.0.0.1.1

.0.0.0.0.0.0.0.0

.1.1.0.0.1.1.1.1

.1.1.1.1.0.0.1.1

.0.0.0.0.0.0.0.0

.1.1.0.0.1.1.1.1

.1.1.1.1.0.0.1.1

CROSSREFS

Sequence in context: A297520 A026394 A004538 * A186029 A083048 A123669

Adjacent sequences:  A146228 A146229 A146230 * A146232 A146233 A146234

KEYWORD

nonn

AUTHOR

R. H. Hardin

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 30 08:40 EDT 2022. Contains 354919 sequences. (Running on oeis4.)