A028849 - OEIS

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A028849

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

0, 0, 6, 0, 27, 0, 91, 45, 417, 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: A167357 A064381 A062254 * A287470 A138704 A005396

Adjacent sequences: A028846 A028847 A028848 * A028850 A028851 A028852

KEYWORD

nonn,more

AUTHOR

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

STATUS

approved