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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
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
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
Sequence in context: A293276 A291609 A291870 * A080034 A378030 A061447
KEYWORD
nonn,more
EXTENSIONS
More detailed name from R. J. Mathar, Jan 16 2020
STATUS
approved