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A322451 Number of unlabeled 3-regular hypergraphs spanning n vertices. 13
1, 0, 0, 1, 3, 29, 2102, 7011184, 1788775603336, 53304526022885280592, 366299663378889804782337225824, 1171638318502622784366970315264281830913536, 3517726593606524901243694560022510194223171115509135178240 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..25

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.

Cf. A006126, A006129, A038041, A299471, A301922, A302374, A302394, A306017, A306021.

Sequence in context: A255597 A319637 A003190 * A213792 A133663 A270480

Adjacent sequences:  A322448 A322449 A322450 * A322452 A322453 A322454

KEYWORD

nonn

AUTHOR

Gus Wiseman, Dec 09 2018

EXTENSIONS

a(12) from Andrew Howroyd, Dec 15 2018

STATUS

approved

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Last modified February 21 01:29 EST 2019. Contains 320364 sequences. (Running on oeis4.)