A039759 Number of edges in the Hasse diagrams for the B-analogs of the partition lattices.

0, 1, 8, 58, 432, 3396, 28384, 252456, 2385280, 23874448, 252380800, 2809461920, 32841595136, 402105388608, 5144478074368, 68625615724160, 952603633463296, 13735016459768064, 205358227932235776, 3179027634604907008, 50881656554805620736, 840901491722391454720, 14332437167995507302400

Offset: 0

Author

Ruedi Suter (suter(AT)math.ethz.ch)

Keywords

• nonn

Links

• R. Suter, Two analogues of a classical sequence, J. Integer Sequences, Vol. 3 (2000), #P00.1.8.

Crossrefs

Edges in the Hasse diagrams for partition lattices: A003128, D-analogs = A039765.

Programs

Mathematica

max = 18; CoefficientList[ Series[1/4*E^x*(E^(4*x) - 1)*E^((1/2)*(E^(2*x) - 1)), {x, 0, max}], x]*Range[0, max]! (* Jean-François Alcover, Oct 04 2013, after e.g.f. *)

PARI

x='x+O('x^66); concat([0], Vec( serlaplace( 1/4*(exp(4*x)-1)*exp(1/2*exp(2*x)+x-1/2) ) ) ) \\ Joerg Arndt, Oct 04 2013

Formula

E.g.f.: 1/4 * (exp(4*x)-1) * exp(1/2*exp(2*x)+x-1/2).