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A263864 Triangle read by rows: T(n,k) (n>=1, k>=1) is the number of posets with n elements whose Hasse diagram has k connected components. 0
1, 1, 1, 3, 1, 1, 10, 4, 1, 1, 44, 13, 4, 1, 1, 238, 60, 14, 4, 1, 1, 1650, 312, 63, 14, 4, 1, 1, 14512, 2075, 328, 64, 14, 4, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Row sums give A000112, n >= 1.

LINKS

Table of n, a(n) for n=1..36.

FindStat - Combinatorial Statistic Finder, The number of connected components of the Hasse diagram for the poset.

Wikipedia, Hasse diagram

EXAMPLE

Triangle begins:

1,

1,1,

3,1,1,

10,4,1,1,

44,13,4,1,1,

...

CROSSREFS

Cf. A000112.

Sequence in context: A268115 A106268 A267655 * A060543 A267751 A185996

Adjacent sequences:  A263861 A263862 A263863 * A263865 A263866 A263867

KEYWORD

nonn,tabl,more

AUTHOR

Christian Stump, Oct 28 2015

STATUS

approved

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Last modified March 26 20:47 EDT 2019. Contains 321535 sequences. (Running on oeis4.)