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A091479
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Number of graphs with n nodes. Nodes and edges labeled each from their own label set.
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2
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1, 1, 2, 16, 1957, 9864101, 3554627472076, 138879579704209680022, 828772446866981044847857913441, 1011182700521015817607065606491025592595137, 325166909258549255903203528672831330994640286650913570126
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,3
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LINKS
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FORMULA
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PROG
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(PARI) a(n)={binomial(n, 2)!*sum(k=0, binomial(n, 2), 1/k!)} \\ Andrew Howroyd, Feb 12 2020
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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a(0)=1 prepended and terms a(10) and beyond from Andrew Howroyd, Feb 12 2020
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STATUS
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approved
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