login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons 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!)
A058338 Number of digraphs with indegree = outdegree at each vertex, or Eulerian digraphs (including disconnected graphs) with n nodes. 7

%I

%S 1,1,2,5,18,111,2292,181519,51294836,48814342597

%N Number of digraphs with indegree = outdegree at each vertex, or Eulerian digraphs (including disconnected graphs) with n nodes.

%D F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 219 (but there is an error).

%D R. C. Read (rcread(AT)math.uwaterloo.ca), email to _N. J. A. Sloane_, 28 August, 2000.

%Y Euler transform of A058337.

%K nonn,nice,more

%O 0,3

%A _N. J. A. Sloane_.

%E a(7) added using A058337 by _Falk H├╝ffner_, Dec 03 2015

%E a(8) and a(9) added using A058337 by _Brendan McKay_, May 05 2019

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 22 04:27 EST 2020. Contains 331133 sequences. (Running on oeis4.)