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A028858 Number of prime unlabeled connected T_0 topologies (i.e., prime T_0 connected homeomorphism classes) on n points. 0
1, 3, 9, 44, 235, 1650, 14502, 163335, 2360675, 43944974 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

REFERENCES

R. Kreminski, "Graphs and matrices in the study of (finite) topological spaces", Missouri J. Mathematical Sciences, Volume 12 (Issue #2, Spring 2000).

LINKS

Table of n, a(n) for n=2..11.

Missouri J. Mathematical Sciences (New web address)

CROSSREFS

Sequence in context: A108239 A218921 A262128 * A058106 A021103 A222662

Adjacent sequences:  A028855 A028856 A028857 * A028859 A028860 A028861

KEYWORD

nonn

AUTHOR

Richard M Kreminski (kremin(AT)boisdarc.tamu-commerce.edu)

STATUS

approved

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Last modified February 26 04:47 EST 2020. Contains 332276 sequences. (Running on oeis4.)