A126741 - OEIS

The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

A126741

Number of connected triangle-free graphs on n nodes with chromatic number 4.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 23, 1085, 75127, 6384013 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,12`
	LINKS	`Table of n, a(n) for n=1..15.` `Keith M. Briggs, Combinatorial Graph Theory`
	CROSSREFS	`See A116079 for further information.` `Sequence in context: A042015 A042012 A128404 * A273477 A202656 A340487` `Adjacent sequences: A126738 A126739 A126740 * A126742 A126743 A126744`
	KEYWORD	`nonn`
	AUTHOR	`N. J. A. Sloane`
	EXTENSIONS	`a(15) from Michael Sollami, Feb 04 2012`
	STATUS	`approved`

Last modified April 17 06:29 EDT 2021. Contains 343059 sequences. (Running on oeis4.)