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URL: https://oeis.org/A084271

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A084271

Number of labeled 3-chromatic (i.e., chromatic number = 3) graphs on n nodes.

3

0, 0, 1, 22, 582, 22377, 1353810, 134222308, 22133512793, 6025984082738, 2662612877308658, 1876486379430019037

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

OFFSET

1,4

LINKS

Table of n, a(n) for n=1..12.

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

FORMULA

a(n) = A084279(n) - A047864(n). - Andrew Howroyd, Dec 02 2018

CROSSREFS

Cf. A047864, A084270, A084272, A084279, A394473.

Sequence in context: A159875 A383630 A240337 * A092086 A373723 A369142

Adjacent sequences: A084268 A084269 A084270 * A084272 A084273 A084274

KEYWORD

nonn,hard,more

AUTHOR

Eric W. Weisstein, May 24 2003

EXTENSIONS

a(7)-a(12) from Andrew Howroyd, Dec 02 2018

STATUS

approved