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%I #16 Apr 18 2017 07:04:11
%S 0,0,2,9,40,215,1446,11893,115844,1302099,16568290,235237937,
%T 3684998208,63113398543,1173013230494,23509415868141,505358483764732,
%U 11597234229683147,282970077651917658,7314780938223880105
%N E.g.f.: (1-exp(x))*log(2-exp(x)).
%C Previous name was: A simple grammar.
%H INRIA Algorithms Project, <a href="http://ecs.inria.fr/services/structure?nbr=814">Encyclopedia of Combinatorial Structures 814</a>
%F E.g.f.: log(-1/(-2+exp(x)))*exp(x)-log(-1/(-2+exp(x)))
%F a(n) ~ (n-1)! / log(2)^n. - _Vaclav Kotesovec_, Sep 30 2013
%p spec := [S,{B=Set(Z,1 <= card),C=Cycle(B),S=Prod(B,C)},labeled]: seq(combstruct[count](spec,size=n), n=0..20);
%t CoefficientList[Series[(1-E^x) * Log[2-E^x], {x, 0, 20}], x]* Range[0, 20]! (* _Vaclav Kotesovec_, Sep 30 2013 *)
%K easy,nonn
%O 0,3
%A encyclopedia(AT)pommard.inria.fr, Jan 25 2000
%E New name, using e.g.f., by _Vaclav Kotesovec_, Sep 30 2013
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