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A126752 Number of biconnected graphs on n nodes with chromatic number 4. 0
0, 0, 0, 1, 2, 17, 189, 3627, 118114, 6530233, 596566067 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

It is possible that the definition should say "connected" rather than "biconnected". Should be rechecked! - Max Alekseyev and Brendan McKay, Jun 17 2008

LINKS

Table of n, a(n) for n=1..11.

Keith M. Briggs, Combinatorial Graph Theory

CROSSREFS

A diagonal of triangle in A126749.

Sequence in context: A242428 A199751 A348766 * A234461 A277768 A333990

Adjacent sequences:  A126749 A126750 A126751 * A126753 A126754 A126755

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Feb 18 2007

EXTENSIONS

a(11) from Michael Sollami, Feb 18 2012

STATUS

approved

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Last modified August 15 23:32 EDT 2022. Contains 356150 sequences. (Running on oeis4.)