A066302 Reduced partially ordered sets (posets) with n labeled elements.

1, 1, 1, 7, 75, 1531, 50673, 2613703, 202180723, 22853355895, 3701983130913, 846741042881779, 270316009546766571, 119343586350194910211, 72325998629777739416209, 59798727157327673157936319

Offset

0,4

References

F. Bergeron, G. Labelle and P. Leroux, Combinatorial Species and Tree-Like Structures, Cambridge, 1998, p. 57 (1.4.70).

Links

Table of n, a(n) for n=0..15.

Index entries for sequences related to posets

Formula

E.g.f.: A(x)=B(x/(1+x)) where B(x) is e.g.f. of A001035.

E.g.f.: A(x)=exp(B(x)) where B(x) is e.g.f. of A066303.

Crossrefs

Sequence in context: A127190 A121316 A220215 * A106162 A285454 A139472

Adjacent sequences: A066299 A066300 A066301 * A066303 A066304 A066305

Keyword

nonn

Author

Christian G. Bower, Dec 12 2001

Status

approved