OFFSET
1,2
LINKS
A. Bacher, Directed and multi-directed animals on the square lattice with next nearest neighbor edges, arXiv 1301.1365, 2013. See M(t).
FORMULA
See Theorem 9 of Bacher (2013) for a generating function.
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Feb 14 2013
STATUS
approved