A207410 Number of connected triangle-free graphs on n nodes with edge chromatic number 4.

0, 0, 0, 0, 1, 4, 25, 136, 772, 4953, 35340, 288335, 2632792, 26726855, 296550560

Offset

1,6

Links

Table of n, a(n) for n=1..15.

Crossrefs

Cf. A207408.

Sequence in context: A273120 A220381 A015533 * A278275 A301836 A275177

Adjacent sequences: A207407 A207408 A207409 * A207411 A207412 A207413

Keyword

nonn,more

Author

Michael Sollami, Feb 17 2012

Status

approved