cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A051504 Number of asymmetric digraphs with n nodes.

Original entry on oeis.org

1, 1, 1, 7, 136, 8001, 1445297, 863488287
Offset: 0

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Author

Vladeta Jovovic

Keywords

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.

Crossrefs

Cf. A000273 (digraphs), A003400 (asymmetric graphs), A030242 (asymmetric relations), A067309.

Formula

a(n) = A000273(n) - A067309(n). - Andrew Howroyd, Dec 06 2020

Extensions

a(6) from Christian G. Bower Dec 15 1999
a(7) from Andrew Howroyd, Dec 06 2020

A030243 Number of nonisomorphic relations with a nontrivial symmetry.

Original entry on oeis.org

0, 0, 4, 34, 580, 23702
Offset: 0

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Author

Christian G. Bower

Keywords

Crossrefs

Equals A000595-A030242.

A030244 Number of connected nonisomorphic relations with no symmetry.

Original entry on oeis.org

1, 2, 5, 60, 2329, 263228
Offset: 0

Views

Author

Christian G. Bower

Keywords

Crossrefs

Inverse Weigh transform of A030242.
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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