A323877 Number of labeled graphs on n nodes with four connected components.

0, 0, 0, 1, 10, 125, 2275, 64673, 3102204, 272277040, 46202044900, 15442093276764, 10171924771814520, 13188852179018387144, 33674263441006260931040, 169522275849148918884400912, 1685048703908907788901122512512, 33116110237646373502366665503208064, 1288337109916947580133035603563656989952, 99320901948403913391024993536094346775110656

Offset

1,5

References

F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, 1973, section 1.2.

Links

Table of n, a(n) for n=1..20.

Marko Riedel et al., Proof of recurrence relation.

Marko Riedel, Maple implementation of memoized recurrence.

Formula

a(n) = A143543(n+1, 4) for n >= 1 and a(0) = 0.

E.g.f.: log(Sum_{q>=0} 2^binomial(q, 2)*z^q/q!)^4/4!.

Crossrefs

Cf. A143543, A323875, A323876.

Sequence in context: A161170 A281595 A097816 * A079609 A101599 A002458

Adjacent sequences: A323874 A323875 A323876 * A323878 A323879 A323880

Keyword

nonn

Author

Marko Riedel, Feb 05 2019

Status

approved