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Number of minimal covers on n objects with 6 members.
1

%I #15 Aug 06 2018 17:45:30

%S 0,0,0,0,0,1,420,100814,18151560,2723868147,359750257020,

%T 43199991728608,4817721638970240,506352103838393813,

%U 50691406225311551700,4872449650707855334482,452435489306282260691640

%N Number of minimal covers on n objects with 6 members.

%H Indranil Ghosh, <a href="/A046167/b046167.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_07">Index entries for linear recurrences with constant coefficients</a>, signature (420,-75586,7555800,-453096049,16299368820,-325685329164,2788484181840).

%F G.f.: x^6/[(1-57x)(1-58x)(1-59x)(1-60x)(1-61x)(1-62x)(1-63x)].

%t CoefficientList[Series[(x^6)/((1-57x)(1-58x)(1-59x)(1-60x)(1-61x)(1-62x)(1-63x)),{x,0,100}],x] (* _Indranil Ghosh_, Feb 20 2017 *)

%t CoefficientList[Series[x^6/Times@@(1-x*Range[57,63]),{x,0,30}],x] (* or *) LinearRecurrence[{420,-75586,7555800,-453096049,16299368820,-325685329164,2788484181840},{0,0,0,0,0,0,1},30] (* _Harvey P. Dale_, Aug 06 2018 *)

%Y Cf. A035348.

%K nonn,easy

%O 1,7

%A _Eric W. Weisstein_