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A005470
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Number of unlabeled planar simple graphs with n nodes.
(Formerly M1252)
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29
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1, 1, 2, 4, 11, 33, 142, 822, 6966, 79853, 1140916, 18681008
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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COMMENTS
| Euler transform of A003094 - Christian G. Bower (bowerc(AT)usa.net)
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REFERENCES
| N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
P. Steinbach, Field Guide to Simple Graphs. Design Lab, Albuquerque NM, 1990.
W. T. Trotter, ed., Planar Graphs, Vol. 9, DIMACS Series in Discrete Mathematics and Theoretical Computer Science, Amer. Math. Soc., 1993.
R. J. Wilson, Introduction to Graph Theory. Academic Press, NY, 1972, p. 162.
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LINKS
| David Wasserman, Table of n, a(n) for n = 1..11
G. Brinkmann, and B.D. McKay, Fast generation of planar graphs, MATCH Commun. Math. Comput. Chem., 58 (2007) 323-357.
G. Brinkmannm and B. McKay, Program for generating these objects..
E. Friedman, Illustration of small graphs
N. J. A. Sloane, Transforms
Eric Weisstein's World of Mathematics, Planar Graph
Index entries for "core" sequences
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EXAMPLE
| a(2)=2 since o o and o-o are the two planar simple graphs on two nodes.
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CROSSREFS
| Cf. A003094 (connected planar graphs), A034889, A039735 (planar graphs by nodes and edges).
Cf. A126201.
Sequence in context: A123469 A123448 A039707 * A123471 A123416 A123406
Adjacent sequences: A005467 A005468 A005469 * A005471 A005472 A005473
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KEYWORD
| nonn,core,nice,hard
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| n=8 term corrected and n=9..11 terms calculated by Brendan McKay (bdm(AT)cs.anu.edu.au)
Terms a(0) - a(10) confirmed by David Applegate (david(AT)research.att.com) and N. J. A. Sloane (njas(AT)research.att.com), Mar 09 2007
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