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A028856 Number of prime unlabeled T_0 topologies (i.e., prime T_0 homeomorphism classes) on n points. 0
2, 5, 13, 63, 308, 2045, 16969, 183216, 2567158, 46749427 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

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: A075738 A076999 A306827 * A013497 A260232 A262366

Adjacent sequences:  A028853 A028854 A028855 * A028857 A028858 A028859

KEYWORD

nonn,nice

AUTHOR

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

STATUS

approved

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Last modified October 18 08:58 EDT 2021. Contains 348067 sequences. (Running on oeis4.)