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A123426 Number of Hoang perfect graphs on n nodes. 0
1, 2, 4, 11, 33, 145, 848, 7111, 77067, 1007506, 15150150, 259469001 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
A graph is called Hoang if its wing graph is bipartite. The wing graph W(G) of a graph G has as its vertices the edges of G and two edges are adjacent in W(G) if there is an induced P4 in G that has these two edges as its ends. - Falk Hüffner, Jun 30 2018
LINKS
S. Hougardy, Classes of perfect graphs, Discr. Math. 306 (2006), 2529-2571.
F. Hüffner, tinygraph, software for generating integer sequences based on graph properties, version 6c1dbe4.
CROSSREFS
Sequence in context: A123453 A351157 A123459 * A277204 A123437 A123435
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 18 2006
EXTENSIONS
a(11)-a(12) added using tinygraph by Falk Hüffner, Jun 30 2018
STATUS
approved

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Last modified February 21 07:44 EST 2024. Contains 370219 sequences. (Running on oeis4.)