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A091479
Number of graphs with n nodes. Nodes and edges labeled each from their own label set.
2
1, 1, 2, 16, 1957, 9864101, 3554627472076, 138879579704209680022, 828772446866981044847857913441, 1011182700521015817607065606491025592595137, 325166909258549255903203528672831330994640286650913570126
OFFSET
0,3
LINKS
FORMULA
a(n) = A000522(A000217(n-1)). - Gerald McGarvey, Nov 17 2007
PROG
(PARI) a(n)={binomial(n, 2)!*sum(k=0, binomial(n, 2), 1/k!)} \\ Andrew Howroyd, Feb 12 2020
CROSSREFS
Row sums of A091478.
Cf. A006125.
Sequence in context: A337070 A326974 A060597 * A016031 A331691 A001309
KEYWORD
nonn
AUTHOR
Christian G. Bower, Jan 13 2004
EXTENSIONS
a(0)=1 prepended and terms a(10) and beyond from Andrew Howroyd, Feb 12 2020
STATUS
approved