login
The OEIS is supported by
the many generous donors to the OEIS Foundation
.
Hints
(Greetings from
The On-Line Encyclopedia of Integer Sequences
!)
A268565
Number of achiral immersions of oriented circle into oriented sphere with 2n double points.
1
1, 1, 5, 15, 97, 592, 4488, 35314, 295379
(
list
;
graph
;
refs
;
listen
;
history
;
text
;
internal format
)
OFFSET
0,3
LINKS
Table of n, a(n) for n=0..8.
Robert Coquereaux and Jean-Bernard Zuber,
Maps, immersions and permutations
, Journal of Knot Theory and Its Ramifications, Vol. 25, No. 8 (2016), 1650047;
arXiv preprint
, arXiv:1507.03163 [math.CO], 2015-2016. See Eq. (17), r_m.
FORMULA
a(n) = 2 *
A008988
(2*n) -
A008986
(2*n). -
Andrey Zabolotskiy
, Jun 05 2024
CROSSREFS
Cf.
A008986
,
A008987
,
A268566
.
Sequence in context:
A184438
A134135
A292279
*
A358197
A121869
A118412
Adjacent sequences:
A268562
A268563
A268564
*
A268566
A268567
A268568
KEYWORD
nonn
,
more
AUTHOR
N. J. A. Sloane
, Mar 03 2016
EXTENSIONS
Name clarified and a(0), a(6)-a(8) added using formula by
Andrey Zabolotskiy
, Jun 08 2024
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 September 14 20:23 EDT 2024. Contains 375929 sequences. (Running on oeis4.)