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 1-6 of 6 results.

A022562 Number of connected claw-free unlabeled graphs on n nodes.

Original entry on oeis.org

1, 1, 2, 5, 14, 50, 191, 881, 4494, 26389, 184749, 1728404, 23805256, 491544474, 14491876320
Offset: 1

Views

Author

Keywords

Crossrefs

Cf. A022563, A022564, A058929, A086991 (Euler transform).

Programs

  • Mathematica
    EulerInvTransform[seq_] := Module[{final = {}}, For[i = 1, i <= Length[seq], i++, AppendTo[final, i*seq[[i]] - Sum[final[[d]]*seq[[i - d]], {d, i - 1}]]]; Table[Sum[MoebiusMu[i/d]*final[[d]], {d, Divisors[i]}]/i, {i, Length[seq]}]];
    A086991 = Cases[Import["https://oeis.org/A086991/b086991.txt", "Table"], {, }][[All, 2]];
    EulerInvTransform[A086991] (* Jean-François Alcover, Aug 20 2019, code due to Gus Wiseman *)

Formula

Inverse Euler transform of A086991. - Andrew Howroyd, Nov 03 2017

Extensions

Corrected and extended by Gordon F. Royle, May 16 2003
Term a(14) added by Gordon F. Royle, Aug 06 2008
Term a(15) added using tinygraph by Falk Hüffner, Jan 12 2016

A057848 Number of 1-connected claw-free cubic graphs with 2n nodes.

Original entry on oeis.org

0, 1, 60, 2520, 453600, 59875200, 13621608000, 8009505504000, 3123380227968000, 1832279324908032000, 2054813830468439040000, 1665031453088810526720000, 1925086583971531588608000000
Offset: 1

Views

Author

N. J. A. Sloane, Jan 12 2001

Keywords

Crossrefs

A058931 Number of 3-connected claw-free cubic graphs with 2n nodes.

Original entry on oeis.org

0, 1, 60, 0, 0, 19958400, 0, 0, 622452999168000, 0, 0, 258520167388849766400000, 0, 0, 675289572271869736778268672000000, 0, 0, 7393367369949286697176489031997849600000000, 0, 0
Offset: 1

Views

Author

N. J. A. Sloane, Jan 12 2001

Keywords

References

  • G.-B. Chae (chaegabb(AT)pilot.msu.edu), E. M. Palmer and R. W. Robinson, Computing the number of Claw-free Cubic Graphs with given Connectivity, preprint, 2001.

Crossrefs

See A058930 for many more terms.

Extensions

Added b-file, N. J. A. Sloane, Feb 08 2012

A058930 Number of 3-connected claw-free cubic graphs with 6n nodes.

Original entry on oeis.org

0, 60, 19958400, 622452999168000, 258520167388849766400000, 675289572271869736778268672000000, 7393367369949286697176489031997849600000000
Offset: 0

Views

Author

N. J. A. Sloane, Jan 12 2001

Keywords

References

  • G.-B. Chae (chaegabb(AT)pilot.msu.edu), E. M. Palmer and R. W. Robinson, Computing the number of Claw-free Cubic Graphs with given Connectivity, preprint, 2001.

Crossrefs

Cf. A058931.

A084657 Number of unlabeled 2-connected claw-free cubic graphs on 2n vertices.

Original entry on oeis.org

0, 1, 1, 1, 1, 3, 2, 4, 8, 10, 16, 34, 51, 99, 198
Offset: 1

Views

Author

Gordon F. Royle, Jun 02 2003

Keywords

Crossrefs

A058932 Number of unlabeled claw-free cubic graphs with 2n nodes and connectivity 1.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 1, 1, 3, 5, 11, 20
Offset: 1

Views

Author

N. J. A. Sloane, Jan 12 2001

Keywords

References

  • G.-B. Chae (chaegabb(AT)pilot.msu.edu), E. M. Palmer and R. W. Robinson, Computing the number of Claw-free Cubic Graphs with given Connectivity, preprint, 2001.
Showing 1-6 of 6 results.