A126738 Number of connected graphs on n nodes with chromatic number 4.

0, 0, 0, 1, 3, 26, 282, 5009, 149551, 7694428, 667036310

Offset: 1

Author

N. J. A. Sloane, Feb 16 2007

Keywords

• nonn

Links

• Keith M. Briggs, Combinatorial Graph Theory

Crossrefs

A diagonal of triangle in A126736.

Extensions

a(11) from Michael Sollami, Jan 29 2012