A019531 Let I_c(n,d) be maximal number of independent sets in d-regular simple connected graphs with n vertices; sequence gives I_c(2n,3).

5, 15, 35, 84, 207, 498, 1202, 2970, 7128, 17202

Offset

2,1

Comments

For each 3-regular graph with 2*n vertices, compute the number of (not necessarily maximal) independent vertex sets in the graph. The value of a(n) is the maximum of these numbers. - Sean A. Irvine, Mar 27 2019

References

Posting to math-fun(AT)cs.arizona.edu by Torsten Sillke (sillke(AT)lh-systems.de).

Links

Table of n, a(n) for n=2..11.

T. Sillke, For more info

Example

For 4 vertices, the only 3-regular graph is K4.  K4 has 5 independents sets (the empty set, and singleton sets for each vertex). Hence, a(2)=5.

Crossrefs

Sequence in context: A330911 A322048 A143695 * A321345 A145454 A292912

Adjacent sequences: A019528 A019529 A019530 * A019532 A019533 A019534

Keyword

nonn,more

Author

Computed by Achim Flammenkamp.

Extensions

Degree corrected and a(10)-a(11) from Sean A. Irvine, Mar 27 2019

Status

approved