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A292623
Number of median graphs on n nodes.
1
1, 1, 1, 3, 4, 11, 23, 69, 178, 567, 1741, 5890, 20005, 71294, 257889, 958595
OFFSET
1,4
LINKS
Eric Weisstein's World of Mathematics, Median Graph
EXAMPLE
n = 1: singleton graph K_1 (1 graph)
n = 2: P_2 = K_2 (1 graph)
n = 3: P_3 (1 graph)
n = 4: K_{1,3}, P_4, square graph P_2 X P_2 (3 graphs)
n = 5: banner graph, fork graph, P_5, S_5 = K_{1,4} (4 graphs)
Here, X denotes the graph Cartesian product
CROSSREFS
Sequence in context: A219514 A131481 A001072 * A077900 A208176 A198443
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, Sep 20 2017
EXTENSIONS
a(11)-a(16) from Brendan McKay, Apr 15 2019
STATUS
approved