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A002887 The minimum number of nodes of a tree with a cutting center of n nodes.
(Formerly M2340 N0923)
5
3, 4, 7, 10, 50 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The cutting number of a node v in a graph G is the number of pairs of nodes {u,w} of G such that u!=v, w!=v, and every path from u to w contains v. The cutting number of a connected graph (including trees as considered here), is the maximum cutting number of any node in the graph. The cutting center of a graph is the set of nodes with cutting number equal to the cutting number of the graph. - Sean A. Irvine, Jan 16 2020

REFERENCES

Frank Harary and Phillip A. Ostrand, How cutting is a cut point?, pp. 147-150 of R. K. Guy et al., editors, Combinatorial Structures and Their Applications (Proceedings Calgary Conference Jun 1969}), Gordon and Breach, NY, 1970.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Table of n, a(n) for n=1..5.

F. Harary and P. A. Ostrand, How cutting is a cut point?, pp. 147-150 of R. K. Guy et al., editors, Combinatorial Structures and Their Applications (Proceedings Calgary Conference Jun 1969}), Gordon and Breach, NY, 1970. [Annotated scan of page 147 only.]

F. Harary and P. A. Ostrand, How cutting is a cut point?, pp. 147-150 of R. K. Guy et al., editors, Combinatorial Structures and Their Applications (Proceedings Calgary Conference Jun 1969}), Gordon and Breach, NY, 1970. [Annotated scan of pages 148, 149 only.]

Frank Harary and Phillip A. Ostrand, The cutting center theorem for trees, Discrete Mathematics, 1 (1971), 7-18.

CROSSREFS

Cf. A002888, A331237.

Sequence in context: A293276 A291609 A291870 * A080034 A061447 A219188

Adjacent sequences:  A002884 A002885 A002886 * A002888 A002889 A002890

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane

EXTENSIONS

More detailed name from R. J. Mathar, Jan 16 2020

STATUS

approved

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Last modified July 14 16:05 EDT 2020. Contains 335729 sequences. (Running on oeis4.)