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%I M1919 N0757 #24 Jul 31 2024 09:14:45
%S 1,2,9,20,670
%N a(n) is the cutting number of the tree corresponding to A002887(n).
%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 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. A002887, A331237.
%K nonn,more
%O 1,2
%A _N. J. A. Sloane_
%E Title improved by _Sean A. Irvine_, Jan 16 2020