[go: up one dir, main page]
login
The OEIS is supported by the many generous donors to the OEIS Foundation.
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A051504
Number of asymmetric digraphs with n nodes.
3
1, 1, 1, 7, 136, 8001, 1445297, 863488287
(list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
REFERENCES
F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 231.
P. K. Stockmeyer, The enumeration of graphs with prescribed automorphism group, Dissertation, Univ. of Michigan, Ann Arbor, 1971.
LINKS
Table of n, a(n) for n=0..7.
FORMULA
a(n) = A000273(n) - A067309(n). - Andrew Howroyd, Dec 06 2020
CROSSREFS
Cf. A000273 (digraphs), A003400 (asymmetric graphs), A030242 (asymmetric relations), A067309.
Sequence in context: A243684 A260535 A220380 * A058881 A100520 A221342
Adjacent sequences: A051501 A051502 A051503 * A051505 A051506 A051507
KEYWORD
hard,nonn,nice
AUTHOR
Vladeta Jovovic
EXTENSIONS
a(6) from Christian G. Bower Dec 15 1999
a(7) from Andrew Howroyd, Dec 06 2020
STATUS
approved

Lookup Welcome Wiki Register Music Plot 2 Demos Index WebCam Contribute Format Style Sheet Transforms Superseeker Recents
The OEIS Community
Maintained by The OEIS Foundation Inc.
Last modified October 5 17:44 EDT 2024. Contains 376565 sequences.
License Agreements, Terms of Use, Privacy Policy