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!)
A235456 Number of non-equivalent (mod D_4) ways to arrange 5 points on an n X n square grid so that no three points are collinear. 6
5, 217, 3192, 27041, 149217, 650566, 2317137, 7124316, 19459757, 48617666, 111797647, 241575473 (list; graph; refs; listen; history; text; internal format)
OFFSET
3,1
COMMENTS
Column 5 of A235453.
Without the restriction "non-equivalent (mod D_4)" the numbers are given by A194190, n >= 3.
LINKS
EXAMPLE
There are a(3) = 5 non-equivalent ways to place 5 points (X) on a 3 X 3 grid:
X . X X . X . X X X X . X . X
X . X X . . X . X X . . X X .
. X . . X X . X . . X X . X .
CROSSREFS
Cf. A235453, A194190, A235454 (3 points), A235455 (4 points), A235457 (6 points), A235458 (7 points)
Sequence in context: A206457 A291806 A119657 * A159808 A159317 A345465
KEYWORD
nonn,more
AUTHOR
Heinrich Ludwig, Jan 12 2014
EXTENSIONS
a(13), a(14) from Heinrich Ludwig, Nov 16 2016
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 25 11:18 EDT 2024. Contains 373701 sequences. (Running on oeis4.)