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A300749
Number of connected squarefree bipartite graphs on n vertices.
2
1, 1, 1, 2, 3, 7, 12, 30, 64, 177, 457, 1403, 4327, 15024, 54730, 219311, 942908, 4426513, 22525015, 124896794, 752933593, 4938212176, 35190683416, 272266028155, 2284292635109
OFFSET
1,4
LINKS
CombOS - Combinatorial Object Server, Generate graphs
Brendan McKay, Inverse Euler transforms needed, message on the SeqFan list, Mar 12 2018.
FORMULA
Inverse Euler transform of A138347.
CROSSREFS
Cf. A138347.
Sequence in context: A305751 A047749 A134565 * A100982 A186009 A299295
KEYWORD
nonn,more
AUTHOR
Alois P. Heinz, Mar 11 2018.
STATUS
approved