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A078672 Number of simple 4-regular 4-edge-connected but not 3-connected plane graphs on n nodes. 2
0, 0, 0, 0, 0, 0, 1, 1, 6, 16, 59, 188, 685, 2412, 8825, 32110, 118505 (list; graph; refs; listen; history; text; internal format)
OFFSET

6,9

LINKS

Table of n, a(n) for n=6..22.

A. Caudron, Classification des noeuds et des enlacements Public. Math. d'Orsay 82. Orsay: Univ. Paris Sud, Dept. Math., 1982.

S. V. Jablan, Ordering Knots

S. V. Jablan, L. M. Radović, and R. Sazdanović, Basic polyhedra in knot theory Kragujevac J. Math., 28 (2005), 155-164.

EXAMPLE

The first such graph has 12 nodes. It is called 12E [Jablan, Radović & Sazdanović, Fig. 2; or Caudron, p. 308c] and looks like that:

    ___________

   /           \

  / O---O   O---O

  |/|\ /|\ /|\ /|

  O | O | O | O |

  |\|/ \|/ \|/ \|

  \ O---O   O---O

   \___________/

CROSSREFS

A078666 = A007022 + this sequence.

Sequence in context: A223028 A091649 A125628 * A219817 A120795 A118640

Adjacent sequences:  A078669 A078670 A078671 * A078673 A078674 A078675

KEYWORD

nonn

AUTHOR

Slavik V. Jablan (jablans(AT)yahoo.com) and Brendan McKay Feb 06 2003

STATUS

approved

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Last modified February 21 17:43 EST 2018. Contains 299414 sequences. (Running on oeis4.)