A066303 Number of connected reduced partially ordered sets (posets) with n labeled elements.

1, 0, 6, 50, 1220, 42122, 2278248, 182111666, 21094774212, 3479970392642, 807001730170592, 260359119927269882, 115887302333840512956, 70677462143507496419690, 58725460618979611312258632

Offset

1,3

Links

Table of n, a(n) for n=1..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 A001927.

E.g.f. A(x)=log(B(x)) where B(x) is e.g.f. of A066302.

Crossrefs

Sequence in context: A058784 A008380 A196905 * A301436 A136383 A043084

Adjacent sequences: A066300 A066301 A066302 * A066304 A066305 A066306

Keyword

nonn

Author

Christian G. Bower, Dec 12 2001

Status

approved