A084272 Number of labeled 4-chromatic (i.e., chromatic number = 4) graphs on n nodes.

0, 0, 0, 1, 65, 5042, 605545, 120653315, 40885736829, 23907349095479, 24391928745798217

Offset

1,5

Links

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

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

Formula

a(n) = A084280(n) - A084279(n). - Andrew Howroyd, Dec 02 2018

Crossrefs

Cf. A084270, A084271, A084279, A084280.

Sequence in context: A078988 A027535 A110900 * A146756 A202386 A294955

Adjacent sequences: A084269 A084270 A084271 * A084273 A084274 A084275

Keyword

nonn,more

Author

Eric W. Weisstein, May 24 2003

Extensions

a(7)-a(11) from Andrew Howroyd, Dec 02 2018

Status

approved