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A123415 Number of cograph contraction perfect graphs on n nodes. 0
1, 2, 4, 11, 33, 139, 737, 5220, 47299, 542268 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
Table of n, a(n) for n=1..10.
S. Hougardy, Home Page
S. Hougardy, Classes of perfect graphs, Discr. Math. 306 (2006), 2529-2571.
CROSSREFS
Sequence in context: A123462 A123463 A123468 * A123469 A123448 A039707
Adjacent sequences: A123412 A123413 A123414 * A123416 A123417 A123418
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Oct 18 2006
STATUS
approved

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Last modified May 13 05:16 EDT 2024. Contains 372498 sequences. (Running on oeis4.)