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A018197 Possible numbers of complements of topologies on 6 points. 0
1, 5, 16, 27, 31, 64 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..5.

J. I. Brown and S. Watson, The number of complements of a topology on n points is at least 2^n (except for some special cases), Discr. Math., 154 (1996), 27-39.

CROSSREFS

Sequence in context: A171787 A227586 A335416 * A061874 A341006 A017449

Adjacent sequences:  A018194 A018195 A018196 * A018198 A018199 A018200

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified June 24 08:43 EDT 2021. Contains 345416 sequences. (Running on oeis4.)