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A126737 Number of connected graphs on n nodes with chromatic number 3. 2
0, 0, 1, 2, 12, 64, 475, 5036, 80947, 2010328, 76115143 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

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

Keith M. Briggs, Combinatorial Graph Theory

CROSSREFS

A diagonal of triangle in A126736.

Sequence in context: A162973 A321989 A226226 * A345697 A097632 A076804

Adjacent sequences:  A126734 A126735 A126736 * A126738 A126739 A126740

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Feb 16 2007

EXTENSIONS

a(11) from Michael Sollami, Jan 29 2012

STATUS

approved

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Last modified October 28 17:59 EDT 2021. Contains 348329 sequences. (Running on oeis4.)