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%I
%S 1,2,8,49,462,6424,129425,3731508,152424420,8780782707,710389021036,
%T 80610570275140,12815915627480695,2855758994821922882,
%U 892194474524889501292,391202163933291014701953,240943718535427829240708786,208683398342300491409959279244
%N Number of minimal covers of n objects.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MinimalCover.html">Minimal Cover</a>
%H Giovanni Resta, <a href="/A046165/a046165.png">Illustration of a(4)=49.</a>
%H Alois P. Heinz, <a href="/A046165/b046165.txt">Table of n, a(n) for n = 1..100</a>
%F E.g.f.: Sum((exp(x)-1)^n*exp(x*(2^n-n-1))/n!, n=0..infinity). - _Vladeta Jovovic_, May 08 2004
%p a:= n-> add (add ((-1)^i* binomial(k,i) *(2^k-1-i)^n, i=0..k)/k!, k=0..n): seq (a(n), n=1..20); # _Alois P. Heinz_, Aug 19 2008
%Y Cf. A035348, A000371, A003465.
%K nonn
%O 1,2
%A _Eric W. Weisstein_
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