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.

A054952 Number of unlabeled semi-strong digraphs on n nodes with pairwise different components.

Original entry on oeis.org

1, 1, 6, 88, 5136, 1052154, 706474926, 1581054875274, 12140605885784816, 328173091958855376334, 31831409045512513121561226, 11234306828778006073392046869300, 14576263867446651299709243211339018934, 70075728362101598938266196294267261948879446
Offset: 1

Views

Author

N. J. A. Sloane, May 24 2000

Keywords

Comments

Weigh transform of A035512. - Andrew Howroyd, Sep 10 2018
A digraph is semi-strong if all its weakly connected components are strongly connected. - Andrew Howroyd, Jan 14 2022

Crossrefs

Programs

Formula

G.f.: -1 + Product_{n > 0} (1 + x^n)^A035512(n). - Andrew Howroyd, Sep 10 2018

Extensions

More terms from Vladeta Jovovic, Mar 11 2003
a(12)-a(14) from Andrew Howroyd, Sep 10 2018

A054953 Number of unlabeled semi-strong digraphs on n nodes with an odd number of pairwise different components.

Original entry on oeis.org

1, 1, 5, 83, 5048, 1047013, 705422455, 1580348377261, 12139024826336632, 328160951350054991463, 31831080872414173375174213, 11234274997368911879051177335450, 14576252633139821208116086572516525403, 70075713785837731364265242597960381223077163
Offset: 1

Views

Author

N. J. A. Sloane, May 24 2000

Keywords

Crossrefs

Programs

Formula

a(n) = (A054952(n) + A054951(n))/2. - Andrew Howroyd, Sep 10 2018

Extensions

More terms from Vladeta Jovovic, Mar 11 2003
a(12)-a(14) from Andrew Howroyd, Sep 10 2018

A054954 Number of unlabeled semi-strong digraphs on n nodes with an even number of pairwise different components.

Original entry on oeis.org

0, 0, 1, 5, 88, 5141, 1052471, 706498013, 1581059448184, 12140608800384871, 328173098339746387013, 31831409094194340869533850, 11234306830091593156638822493531, 14576263867574000953696306880725802283
Offset: 1

Views

Author

N. J. A. Sloane, May 24 2000

Keywords

Crossrefs

Programs

Formula

a(n) = (A054952(n) - A054951(n))/2. - Andrew Howroyd, Sep 10 2018

Extensions

More terms from Vladeta Jovovic, Mar 11 2003
a(12)-a(14) from Andrew Howroyd, Sep 10 2018
Showing 1-3 of 3 results.