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A052877
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E.g.f.: exp(x)-1+log(-1/(-2+exp(x))).
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0
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0, 2, 3, 7, 27, 151, 1083, 9367, 94587, 1091671, 14174523, 204495127, 3245265147, 56183135191, 1053716696763, 21282685940887, 460566381955707, 10631309363962711, 260741534058271803, 6771069326513690647
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OFFSET
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0,2
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COMMENTS
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Previous name was: A simple grammar.
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LINKS
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FORMULA
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E.g.f.: exp(x)-1+log(-1/(-2+exp(x)))
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MAPLE
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spec := [S, {B=Set(Z, 1 <= card), C=Cycle(B), S=Union(B, C)}, labeled]: seq(combstruct[count](spec, size=n), n=0..20);
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MATHEMATICA
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CoefficientList[Series[E^x-1+Log[-1/(-2+E^x)], {x, 0, 20}], x]* Range[0, 20]! (* Vaclav Kotesovec, Sep 30 2013 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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encyclopedia(AT)pommard.inria.fr, Jan 25 2000
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EXTENSIONS
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STATUS
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approved
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