A003317 Number of unlabeled minimally 2-connected graphs with n nodes (also called "blocks").

1, 1, 2, 3, 6, 12, 28, 68, 184, 526, 1602, 5075, 16711, 56428, 195003, 685649, 2447882, 8850157, 32359428, 119492766, 445236635, 1672636369, 6331624545, 24138404479, 92640942148, 357805122286, 1390318899884, 5433781135206

Offset: 3

Author

N. J. A. Sloane

Keywords

• nonn
• nice

Comments

The Pootheri references also contain the edge breakups for each term.

References

• A. M. Hobbs, A catalog of minimal blocks, J. Res. National Bureau Standards, B 77 (1973), 53-60.
• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Audace A. V. Dossou-Olory, Cut and pendant vertices and the number of connected induced subgraphs of a graph, arXiv:1910.04552 [math.CO], 2019.
• A. M. Hobbs, A catalog of minimal blocks, J. Res. National Bureau Standards, B 77 (1973), 53-60. (Annotated scanned copy)
• Hu, Guan Zhang; Liu, Guo Qing; Liu, Shi; He, Jian Ping; Enumeration of minimally 2-connected graphs by means of group theory, (Chinese) Acta Math. Appl. Sinica 12 (1989), no. 2, 164-173.
• S. K. Pootheri, Counting classes of labeled 2-connected graphs, M.S. Dissertation, University of Georgia, 2000.
• S. K. Pootheri, Counting classes of labeled 2-connected graphs, M.S. Thesis, University of Georgia, 2000. [Local copy]
• S. K. Pootheri, Characterizing and counting classes of unlabeled 2-connected graphs, Ph. D. Dissertation, University of Georgia, 2000.
• S. K. Pootheri, Characterizing and counting classes of unlabeled 2-connected graphs, Ph. D. Dissertation, University of Georgia, 2000. [Local copy]

Crossrefs

Cf. A054316, A054317, A002218.

Extensions

More terms from Sridar K. Pootheri (sridar(AT)math.uga.edu), Feb 25 2000