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A079566 Number of unlabeled, connected graphs on n vertices which have no induced subgraph isomorphic to a C4 (cycle on 4 vertices.) 0
1, 1, 2, 5, 16, 63, 313, 2014, 16724, 178608, 2422046, 41049952, 855470220 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..13.

Z. Blázsik, M. Hujter, M. Pluhár and Z. Tuza, Graphs with no C4 and 2K2, Discrete Math. 115 (1993) 51-55.

CROSSREFS

Sequence in context: A022494 A136127 A111004 * A059685 A000112 A205498

Adjacent sequences:  A079563 A079564 A079565 * A079567 A079568 A079569

KEYWORD

more,nonn

AUTHOR

Jim Nastos, Jan 24 2003

EXTENSIONS

More terms from Falk Hüffner, Jan 11 2016, computed using https://github.com/falk-hueffner/tinygraph (nauty based) version 8489dde

STATUS

approved

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Last modified December 18 05:48 EST 2018. Contains 318215 sequences. (Running on oeis4.)