A287023 - OEIS

A287023

Number of simple disconnected weakly perfect graphs on n vertices.

0, 1, 2, 5, 13, 43, 186, 1187, 13006, 270900, 11286208

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

COMMENTS

First differs from A287008 (number of simple disconnected graphs with equal chromatic and fractional chromatic number) at a(8).

LINKS

Eric Weisstein's World of Mathematics, Disconnected Graph

Eric Weisstein's World of Mathematics, Weakly Perfect Graph

FORMULA

a(n) = A198634(n) - A287009(n).

CROSSREFS

Cf. A198634 (number of not necessarily connected simple weakly perfect graphs).

Cf. A287009 (number of not connected simple weakly perfect graphs).

Cf. A287008 (number of simple disconnected graphs with equal chromatic and fractional chromatic number).

KEYWORD

nonn,more

AUTHOR

EXTENSIONS

a(11) from formula by Falk Hüffner, Aug 13 2017

STATUS

approved