login
This site is supported by donations to The OEIS Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A170946 Number of sensed unrooted maps with n edges. 3
2, 5, 20, 107, 870, 9436, 122840, 1863359, 32019826, 613981447, 12989756316, 300559406027, 7550660328494, 204687564072918, 5955893472990664, 185158932576089787, 6125200100394894738, 214837724735760642773 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also number of "dessins d'enfants" with n edges. - Mark van Hoeij, Jan 23 2011

LINKS

Antonio Breda d'Azevedo, Alexander Mednykh and Roman Nedela, Table of n, a(n) for n = 1..30

Antonio Breda d'Azevedo, Alexander Mednykh and Roman Nedela, Enumeration of maps regardless of genus: Geometric approach, Discrete Mathematics, Volume 310, 2010, Pages 1184-1203.

N. M. Adrianov, N. Ya. Amburg, V. A. Dremov, Yu. A. Levitskaya, E. M. Kreines, Yu. Yu. Kochetkov, V. F. Nasretdinova and G. B. Shabat, Catalog of dessins d'enfants with <= 4 edges, arXiv:0710.2658 [math.AG]

R. de Mello Koch, S. Ramgoolam, Strings from Feynman graph counting: without large N, arXiv:1110.4858 (2012), (D.10)

CROSSREFS

Sequence in context: A227096 A152562 A006867 * A296727 A201224 A305922

Adjacent sequences:  A170943 A170944 A170945 * A170947 A170948 A170949

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Feb 21 2010

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 18 03:13 EST 2019. Contains 319260 sequences. (Running on oeis4.)