Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A014501
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A014501 Number of graphs with loops, having unlabeled (non-isolated) nodes and n labeled edges. +0
3
1, 2, 7, 43, 403, 5245, 89132, 1898630, 49209846, 1517275859, 54669946851, 2269075206395, 107199678164289, 5707320919486026, 339510756324234931, 22400182888853554291, 1628654713107465602783, 129754625253841669625051 (list; graph; listen)
OFFSET

0,2

REFERENCES

G. Labelle, Counting enriched multigraphs..., Discrete Math., 217 (2000), 237-248.

G. Paquin, D\'enombrement de multigraphes enrichis, M\'emoire, Math. Dept., Univ. Qu\'ebec \`a Montr\'eal, 2004.

FORMULA

E.g.f.: exp(-1+x/2)*Sum((1+x)^binomial(n+1, 2)/n!, n=0..infinity) [probably in the Labelle paper] - Vladeta Jovovic (vladeta(AT)Eunet.yu), Apr 27 2004

CROSSREFS

Cf. A020554, A020555, A014500.

Adjacent sequences: A014498 A014499 A014500 this_sequence A014502 A014503 A014504

Sequence in context: A086331 A121418 A136734 this_sequence A011835 A103084 A041507

KEYWORD

nonn

AUTHOR

Simon Plouffe, gilbert(AT)lacim.uqam.ca (Gilbert Labelle).

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified October 7 14:39 EDT 2008. Contains 144666 sequences.


AT&T Labs Research