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A018195
Possible numbers of complements of topologies on 4 points.
0
1, 3, 4, 7, 12, 14, 15, 16
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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:
A244819
A305185
A083561
*
A086417
A051215
A192112
Adjacent sequences:
A018192
A018193
A018194
*
A018196
A018197
A018198
KEYWORD
nonn
,
more
AUTHOR
N. J. A. Sloane
.
STATUS
approved
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Last modified August 21 12:27 EDT 2024. Contains 375353 sequences. (Running on oeis4.)