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A301481 Number of unlabeled uniform hypergraphs spanning n vertices. 5
1, 1, 1, 2, 4, 12, 58 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

A hypergraph is uniform if all edges have the same size.

LINKS

Table of n, a(n) for n=0..6.

EXAMPLE

Non-isomorphic representatives of the a(4) = 12 hypergraphs:

  {{1,2,3,4}}

  {{1,2},{3,4}}

  {{1},{2},{3},{4}}

  {{1,3,4},{2,3,4}}

  {{1,3},{2,4},{3,4}}

  {{1,4},{2,4},{3,4}}

  {{1,2,4},{1,3,4},{2,3,4}}

  {{1,2},{1,3},{2,4},{3,4}}

  {{1,4},{2,3},{2,4},{3,4}}

  {{1,3},{1,4},{2,3},{2,4},{3,4}}

  {{1,2,3},{1,2,4},{1,3,4},{2,3,4}}

  {{1,2},{1,3},{1,4},{2,3},{2,4},{3,4}}

CROSSREFS

Cf. A003465, A038041, A055621, A298422, A301920, A301922, A306017-A306021.

Sequence in context: A099928 A000568 A177921 * A128648 A128646 A155747

Adjacent sequences:  A301478 A301479 A301480 * A301482 A301483 A301484

KEYWORD

nonn,more

AUTHOR

Gus Wiseman, Jun 19 2018

STATUS

approved

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Last modified March 26 06:55 EDT 2019. Contains 321481 sequences. (Running on oeis4.)