A076280 Number of 4-chromatic (i.e., chromatic number equals 4) simple graphs on n nodes.

0, 0, 0, 1, 4, 31, 318, 5366, 155291, 7855628, 675054876

Offset

1,5

Links

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

Keith M. Briggs, Combinatorial Graph Theory

Eric Weisstein's World of Mathematics, n-Chromatic Graph

Crossrefs

Column k=4 of A084268.

Cf. A076278, A076279, A076281, A076282.

Sequence in context: A243312 A349739 A359621 * A141005 A122400 A107725

Adjacent sequences: A076277 A076278 A076279 * A076281 A076282 A076283

Keyword

nonn,more

Author

Eric W. Weisstein, Oct 06 2002

Extensions

a(10) from Keith Briggs, Feb 24 2006

a(11) from Michael Sollami, Jan 28 2012

Status

approved