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%I #19 Jun 01 2014 02:14:52
%S 1,7,70,854,12068,191996,3374392,64635640,1335753664,29548086848,
%T 695221579136,17307703505792,453917707384960,12494500081323904,
%U 359807967643449088,10809816056831434496,337981832271282386432
%N Number of labeled servers of dimension 7.
%H Vincenzo Librandi, <a href="/A027394/b027394.txt">Table of n, a(n) for n = 0..200</a>
%H R. Donaghey, <a href="http://dx.doi.org/10.1016/0097-3165(76)90060-1">Binomial self-inverse sequences and tangent coefficients</a>, J. Combin. Theory, Series A, 21 (1976), 155-163.
%F E.g.f.: exp( sum( ((1+x)^i-1)/i, i=1..7 ) ).
%t Table[n!*SeriesCoefficient[E^(Sum[((1 + x)^i - 1)/i, {i, 1, 7}]), {x, 0, n}], {n, 0, 20}] (* _Vincenzo Librandi_, Dec 31 2012 *)
%K nonn
%O 0,2
%A _Olivier Gérard_