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A301922 Regular triangle where T(n,k) is the number of unlabeled k-uniform hypergraphs spanning n vertices. 9
1, 1, 1, 1, 2, 1, 1, 7, 3, 1, 1, 23, 29, 4, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Triangle begins:

   1

   1   1

   1   2   1

   1   7   3   1

   1  23  29   4   1

The T(4,2) = 7 hypergraphs:

  {{1,2},{3,4}}

  {{1,3},{2,4},{3,4}}

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

CROSSREFS

Row sums are A301481. Second column is A002494.

Cf. A003465, A055621, A298422, A298426, A299471, A301481, A301920, A306017-A306021.

Sequence in context: A178234 A259175 A297431 * A144510 A143670 A169730

Adjacent sequences:  A301919 A301920 A301921 * A301923 A301924 A301925

KEYWORD

nonn,tabl,more

AUTHOR

Gus Wiseman, Jun 19 2018

STATUS

approved

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Last modified February 21 04:18 EST 2019. Contains 320371 sequences. (Running on oeis4.)