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A126730 Number of graphs on n nodes with edge chromatic number 4. 0
0, 0, 0, 0, 10, 58, 347, 2130, 14039, 103927 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..10.

Keith M. Briggs, Combinatorial Graph Theory

CROSSREFS

A diagonal of triangle in A123962.

Sequence in context: A242202 A125320 A321112 * A126478 A223470 A044148

Adjacent sequences:  A126727 A126728 A126729 * A126731 A126732 A126733

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Feb 16 2007

STATUS

approved

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Last modified December 3 22:32 EST 2021. Contains 349468 sequences. (Running on oeis4.)