A126752 - OEIS

A126752

Number of biconnected graphs on n nodes with chromatic number 4.

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`

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