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A123448 Number of permutation perfect graphs on n nodes. 0
1, 2, 4, 11, 33, 142, 776, 5699, 50723, 524572, 6037518, 75912033, 1029974969, 14974215412 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

All permutation graphs are perfect. - Jakub Jablonski, Sep 07 2020

LINKS

Table of n, a(n) for n=1..14.

S. Hougardy, Home Page

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

CROSSREFS

Sequence in context: A123468 A123415 A123469 * A039707 A005470 A123471

Adjacent sequences:  A123445 A123446 A123447 * A123449 A123450 A123451

KEYWORD

nonn,more,hard

AUTHOR

N. J. A. Sloane, Oct 18 2006

EXTENSIONS

a(11) from Jakub Jablonski, Sep 07 2020

a(12)-a(14) from Tom Johnston, Oct 25 2020

STATUS

approved

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Last modified November 29 19:26 EST 2020. Contains 338769 sequences. (Running on oeis4.)