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A052431 Number of perfect simple undirected graphs on n nodes. 4
1, 2, 4, 11, 33, 148, 906, 8887, 136756, 3269264, 115811998, 5855499195, 410580177259 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

A. Brandstaedt, V. B. Le and J. P. Spinrad, Graph Classes: A Survey, SIAM Publications, 1999.

LINKS

Table of n, a(n) for n=1..13.

S. Hougardy, Home Page

S. Hougardy, Classes of perfect graphs, Discr. Math. 306 (2006), 2529-2571.

Florian Kohl, McCabe Olsen, Raman Sanyal, Unconditional reflexive polytopes, arXiv:1906.01469 [math.CO], 2019.

Brendan McKay, Perfect graphs

Eric Weisstein's World of Mathematics, Perfect Graph

CROSSREFS

Cf. A052433.

Sequence in context: A123451 A123470 A123450 * A076316 A304125 A082104

Adjacent sequences:  A052428 A052429 A052430 * A052432 A052433 A052434

KEYWORD

nonn,hard,more

AUTHOR

Eric W. Weisstein

EXTENSIONS

McKay link, giving more terms, supplied by Vladeta Jovovic, Jan 31 2003

a(12) added by N. J. A. Sloane from the Hougardy paper, Oct 17 2006

a(13) added by Brendan McKay, Mar 11 2018

STATUS

approved

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Last modified February 21 18:37 EST 2020. Contains 332107 sequences. (Running on oeis4.)