OFFSET
1,2
LINKS
N. Calkin, C. Merino, S. Noble and M. Noy, Improved Bounds for the Number of Forests and Acyclic Orientations in the Square Lattice, The Electronic Journal of Combinatorics, Volume 10(1), 2003, #R4.
A. Pönitz, Über eine Methode zur Konstruktion von Algorithmen für die Berechnung von Invarianten in endlichen ungerichteten Hypergraphen, PhD Thesis (2004) C.3.
Peter Tittmann, More Results [Gives a(1)-a(14)]
CROSSREFS
KEYWORD
nonn
AUTHOR
Andre Poenitz [André Pönitz], Peter Tittmann (poenitz(AT)htwm.de), Mar 03 2003
EXTENSIONS
a(10) from Alois P. Heinz, Dec 21 2013
STATUS
approved