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Number of minimal covers on n objects with 5 members.
4

%I #15 Feb 21 2017 02:39:34

%S 0,0,0,0,1,171,17066,1298346,83384427,4762648737,249485204452,

%T 12226539786912,568267449522773,25296121946918823,1086375882592194558,

%U 45264846407024660598,1837809636559394481439,72965749033508656346829

%N Number of minimal covers on n objects with 5 members.

%H Indranil Ghosh, <a href="/A046166/b046166.txt">Table of n, a(n) for n = 1..100</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MinimalCover.html">Minimal Cover.</a>

%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (171,-12175,461985,-9853624,112007964,-530122320).

%F G.f.: x^5/[(1-26x)(1-27x)(1-28x)(1-29x)(1-30x)(1-31x)].

%t LinearRecurrence[{171,-12175,461985,-9853624,112007964,-530122320},{0,0,0,0,1,171},18] (* or *) CoefficientList[Series[(x^5)/((1-26x)(1-27x)(1-28x)(1-29x)(1-30x)(1-31x)) ,{x,0,100}],x] (* _Indranil Ghosh_, Feb 20 2017 *)

%Y Cf. A035348.

%K nonn

%O 1,6

%A _Eric W. Weisstein_