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A322451 Number of unlabeled 3-uniform hypergraphs spanning n vertices. 14
1, 0, 0, 1, 3, 29, 2102, 7011184, 1788775603336, 53304526022885280592, 366299663378889804782337225824, 1171638318502622784366970315264281830913536, 3517726593606524901243694560022510194223171115509135178240 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,5
COMMENTS
3-uniform means that every edge consists of 3 vertices. - Brendan McKay, Sep 03 2023
LINKS
EXAMPLE
Non-isomorphic representatives of the a(5) = 29 hypergraphs:
{{125}{345}}
{{123}{245}{345}}
{{135}{245}{345}}
{{145}{245}{345}}
{{123}{145}{245}{345}}
{{124}{135}{245}{345}}
{{125}{135}{245}{345}}
{{134}{235}{245}{345}}
{{145}{235}{245}{345}}
{{123}{124}{135}{245}{345}}
{{123}{145}{235}{245}{345}}
{{124}{134}{235}{245}{345}}
{{134}{145}{235}{245}{345}}
{{135}{145}{235}{245}{345}}
{{145}{234}{235}{245}{345}}
{{123}{124}{134}{235}{245}{345}}
{{123}{134}{145}{235}{245}{345}}
{{123}{145}{234}{235}{245}{345}}
{{124}{135}{145}{235}{245}{345}}
{{125}{135}{145}{235}{245}{345}}
{{135}{145}{234}{235}{245}{345}}
{{123}{124}{135}{145}{235}{245}{345}}
{{124}{135}{145}{234}{235}{245}{345}}
{{125}{135}{145}{234}{235}{245}{345}}
{{134}{135}{145}{234}{235}{245}{345}}
{{123}{124}{135}{145}{234}{235}{245}{345}}
{{125}{134}{135}{145}{234}{235}{245}{345}}
{{124}{125}{134}{135}{145}{234}{235}{245}{345}}
{{123}{124}{125}{134}{135}{145}{234}{235}{245}{345}}
CROSSREFS
First differences of A000665.
Sequence in context: A255597 A319637 A003190 * A213792 A133663 A270480
KEYWORD
nonn
AUTHOR
Gus Wiseman, Dec 09 2018
EXTENSIONS
a(12) from Andrew Howroyd, Dec 15 2018
Name corrected by Brendan McKay, Sep 03 2023
STATUS
approved

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Last modified March 28 18:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)