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A099438 Number of simple connected class-2 graphs on n nodes. 2
0, 0, 1, 0, 4, 3, 32, 67, 930 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..9.

Gordon Royle, Small Graphs: Class 2 Graphs.

Eric Weisstein's World of Mathematics, Class 2 Graph

FORMULA

a(n) = A001349(n) - A099436(n). - Andrew Howroyd, Sep 03 2019

CROSSREFS

Cf. A001349 (number of connected graphs on n nodes).

Cf. A099437 (number of simple class-2 graphs on n nodes).

Cf. A099436 (number of connected class-1 graphs on n nodes).

Sequence in context: A127138 A064081 A211364 * A002178 A013558 A161000

Adjacent sequences:  A099435 A099436 A099437 * A099439 A099440 A099441

KEYWORD

nonn,more

AUTHOR

Eric W. Weisstein, Oct 15 2004

STATUS

approved

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Last modified February 25 11:34 EST 2020. Contains 332233 sequences. (Running on oeis4.)