A018196 - OEIS

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A018196

Possible numbers of complements of topologies on 5 points.

%I #13 Dec 12 2015 02:08:30

%S 1,4,8,9,15,32

%N Possible numbers of complements of topologies on 5 points.

%H J. I. Brown and S. Watson, <a href="http://dx.doi.org/10.1016/0012-365X(95)00004-G">The number of complements of a topology on n points is at least 2^n (except for some special cases)</a>, Discr. Math., 154 (1996), 27-39.

%Y Cf. A000798.

%K nonn,more,fini

%O 0,2

%A _N. J. A. Sloane_