A028850 - OEIS

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A028850

Number of composite unlabeled T_0 topologies (i.e., composite T_0 homeomorphism classes) on n points.

0, 0, 3, 0, 10, 0, 30, 15, 126, 0

(list; graph; refs; listen; history; text; internal format)

OFFSET

2,3

LINKS

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

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

CROSSREFS

Sequence in context: A375991 A094472 A347999 * A138364 A095364 A094052

Adjacent sequences: A028847 A028848 A028849 * A028851 A028852 A028853

KEYWORD

nonn,more

AUTHOR

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

STATUS

approved