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A018204 Possible numbers of complements of topologies on 13 points. 0
1, 12, 121, 1000, 2048, 4095, 6561, 8192 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..7.

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: A037097 A299823 A222634 * A176779 A098297 A037543

Adjacent sequences:  A018201 A018202 A018203 * A018205 A018206 A018207

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified December 15 14:37 EST 2019. Contains 329999 sequences. (Running on oeis4.)