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.

A296525 Maximal diameter of connected k-regular graphs on 2*n nodes written as array T(n,k), 2 <= k < 2*n.

Original entry on oeis.org

2, 1, 3, 2, 2, 1, 4, 3, 2, 2, 2, 5, 5, 3, 2, 2, 2, 2, 1, 6, 6, 4, 3, 2, 2, 2, 2, 2, 1, 7, 8, 5, 5, 3, 2, 2, 2, 2, 2, 2, 1, 8, 9, 7, 5
Offset: 2

Views

Author

Hugo Pfoertner, Dec 14 2017

Keywords

Comments

The results were found by applying the Floyd-Warshall algorithm to the output of Markus Meringer's GenReg program.

Examples

			Table starts:
Degree = 2  3  4  5  6  7  8  9
n= 4 :   2  1
n= 6 :   3  2  2  1
n= 8 :   4  3  2  2  2  1
n=10 :   5  5  3  2  2  2  2  1
...
See example in A296526 for a complete illustration of the irregular table.

Links

Crossrefs

Cf. A068934, A294732 (2nd column of table), A294733, A296524, A296526, A296621.

Extensions

a(46) corresponding to the quintic graph on 16 nodes from Hugo Pfoertner, Dec 19 2017

A204329 Irregular triangle read by rows: T(n,k) (n >= 2) is the number of cubic graphs on 2*n nodes with diameter k.

Original entry on oeis.org

1, 0, 2, 0, 2, 3, 0, 1, 15, 2, 1, 0, 0, 34, 43, 6, 2, 0, 0, 34, 351, 93, 24, 6, 1, 0, 0, 14, 2167, 1499, 261, 101, 14, 4, 0, 0, 1, 12301, 22992, 4400, 1229, 310, 55, 12, 1, 0, 0, 1, 57628, 338356, 90870, 17281, 5145, 948, 220, 36, 4, 0, 0, 0, 185836, 4692045, 2013271, 321788, 84159, 17894, 3516, 799, 118, 20, 1
Offset: 2

Views

Author

N. J. A. Sloane, Jan 14 2012

Keywords

Comments

The number of terms in each row (the maximal diameter) begins 1,2,3,5,6,8,... . I don't know how this sequence continues.
The maximal diameter is now provided in A294732, taken from Gordon Royle's Cubic Graphs page. - Hugo Pfoertner, Dec 13 2017

Examples

			Triangle begins:
1
0 2
0 2 3
0 1 15 2 1
0 0 34 43 6 2
0 0 34 351 93 24 6 1
0 0 14 2167 1499 261 101 14 4
0 0 1 12301 22992 4400 1229 310 55 12 1
0 0 1 57628 338356 90870 17281 5145 948 220 36 4
0 0 0 185836 4692045 2013271 321788 84159 17894 3516 799 118 20 1
0 0 0 341797 62398297 45891477 7325370 1558408 344829 63072 14082 2665 466 66 6
0 0 0 298821 805690750 1059325766 187592813 32867106 7116021 1271737 253582 52710 9503 1779 245 30 1

Links

Crossrefs

Cf. A002851, A294732.

Extensions

Extended using data from Gordon Royle's Cubic Graphs page by Hugo Pfoertner, Dec 13 2017

A294733 Maximal diameter of connected (2*k)-regular graphs on 2*n+1 nodes written as triangular array T(n,k), 1 <= k <= n.

Original entry on oeis.org

1, 2, 1, 3, 2, 1, 4, 2, 2, 1, 5, 4, 2, 2, 1, 6, 5, 2, 2, 2, 1, 7, 6, 4, 2, 2, 2, 1, 8
Offset: 1

Views

Author

Hugo Pfoertner, Dec 14 2017

Keywords

Comments

The results were found by applying the Floyd-Warshall algorithm to the output of Markus Meringer's GenReg program.

Examples

			Table starts:
Degree= 2   4   6   8  10  12  14  16
n= 3  : 1
n= 5  : 2   1
n= 7  : 3   2   1
n= 9  : 4   2   2   1
n=11  : 5   4   2   2   1
n=13  : 6   5   2   2   2   1
n=15  : 7   6   4   2   2   2   1
n=17  : 8 >=7 >=4   2   2   2   2   1

Links

Crossrefs

Cf. A068934, A294732, A296524, A296525, A296526.
Showing 1-3 of 3 results.

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

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