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 1-7 of 7 results.

A241706 Number of simple connected graphs on n nodes with diameter 2.

Original entry on oeis.org

0, 0, 1, 4, 14, 59, 373, 4154, 91518, 4116896
Offset: 1

Views

Author

Travis Hoppe and Anna Petrone, Apr 27 2014

Keywords

Crossrefs

Column k=2 of A294522.
Simple connected graphs of diameter k: A241706, A241707, A241708, A241709, A241710.

A241707 Number of simple connected graphs on n nodes with diameter 3.

Original entry on oeis.org

0, 0, 0, 1, 5, 43, 387, 5797, 148229, 6959721
Offset: 1

Views

Author

Travis Hoppe and Anna Petrone, Apr 27 2014

Keywords

Crossrefs

Column k=3 of A294522.
Simple connected graphs of diameter k: A241706, A241707, A241708, A241709, A241710.

A241708 Number of simple connected graphs on n nodes with diameter 4.

Original entry on oeis.org

0, 0, 0, 0, 1, 8, 82, 1027, 19320, 598913
Offset: 1

Views

Author

Travis Hoppe and Anna Petrone, Apr 27 2014

Keywords

Crossrefs

Column k=4 of A294522.
Cf. simple connected graph of diameter k A241706, A241707, A241708, A241709, A241710.

A241709 Number of simple connected graphs on n nodes with diameter 5.

Original entry on oeis.org

0, 0, 0, 0, 0, 1, 9, 125, 1818, 37856
Offset: 1

Views

Author

Travis Hoppe and Anna Petrone, Apr 27 2014

Keywords

Crossrefs

Column k=5 of A294522.
Cf. simple connected graph of diameter k A241706, A241707, A241708, A241709, A241710.

A241710 Number of simple connected graphs on n nodes with diameter 6.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 1, 12, 180, 2928
Offset: 1

Views

Author

Travis Hoppe and Anna Petrone, Apr 27 2014

Keywords

Crossrefs

Column k=6 of A294522.
Cf. simple connected graph of diameter k A241706, A241707, A241708, A241709, A241710.

A324244 Triangle read by rows: T(n,k) is the number of simple connected graphs on n nodes with k peripheral nodes.

Original entry on oeis.org

1, 0, 1, 0, 1, 1, 0, 2, 2, 2, 0, 5, 4, 7, 5, 0, 25, 20, 16, 23, 28, 0, 185, 146, 119, 57, 123, 223, 0, 2459, 1728, 1523, 948, 405, 903, 3151, 0, 58156, 36109, 32119, 24637, 13927, 4713, 11746, 79673, 0, 2617378, 1446609, 1304109, 1026845, 723871, 353620, 110734, 279535, 3853870
Offset: 1

Views

Author

Andrew Howroyd, Sep 02 2019

Keywords

Comments

The peripheral nodes of a graph are those with eccentricity equal to the diameter.

Examples

			Triangle begins:
  1;
  0,     1;
  0,     1,     1;
  0,     2,     2,     2;
  0,     5,     4,     7,     5;
  0,    25,    20,    16,    23,    28;
  0,   185,   146,   119,    57,   123,  223;
  0,  2459,  1728,  1523,   948,   405,  903,  3151;
  0, 58156, 36109, 32119, 24637, 13927, 4713, 11746, 79673;
  ...
		

Crossrefs

Row sums give A001349.
Column k=2 is A324263.
Rightmost diagonal is A324264.

A324239 Irregular triangle read by rows: T(n,k) is the number of simple connected graphs on n nodes with radius k, (0 <= k <= floor(n/2)).

Original entry on oeis.org

1, 0, 1, 0, 2, 0, 4, 2, 0, 11, 10, 0, 34, 76, 2, 0, 156, 682, 15, 0, 1044, 9864, 207, 2, 0, 12346, 245518, 3197, 19, 0, 274668, 11366961, 74614, 326, 2
Offset: 1

Views

Author

Andrew Howroyd, Sep 02 2019

Keywords

Examples

			Triangle begins:
  1;
  0,      1;
  0,      2;
  0,      4,        2;
  0,     11,       10;
  0,     34,       76,     2;
  0,    156,      682,    15;
  0,   1044,     9864,   207,   2;
  0,  12346,   245518,  3197,  19;
  0, 274668, 11366961, 74614, 326, 2;
  ...
		

Crossrefs

Row sums give A001349.
Columns k=1..2 are A000088(n-1), A324061.
Showing 1-7 of 7 results.