A002887 - OEIS

%I M2340 N0923 #42 Jul 31 2024 09:20:26

%S 3,4,7,10,50

%N The minimum number of nodes of a tree with a cutting center of n nodes.

%C 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

%D 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.

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

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

%H F. Harary and P. A. Ostrand, <a href="/A002887/a002887.pdf">How cutting is a cut point?</a>, 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.]

%H F. Harary and P. A. Ostrand, <a href="/A002887/a002887_1.pdf">How cutting is a cut point?</a>, 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.]

%H Frank Harary and Phillip A. Ostrand, <a href="https://doi.org/10.1016/0012-365X(71)90003-3">The cutting center theorem for trees</a>, Discrete Mathematics, 1 (1971), 7-18.

%Y Cf. A002888, A331237.

%K nonn,more

%O 1,1

%A _N. J. A. Sloane_

%E More detailed name from _R. J. Mathar_, Jan 16 2020