OFFSET
0,2
COMMENTS
a(n) is the number of elements in the sphere of radius n in the Cayley graph of Richard Thompson's group F with the standard generating set {x_0, x_1}.
REFERENCES
M. Elder, E. Fusy, A. Rechnitzer, Counting elements and geodesics in Thompson's Group F, J. Alg. 324 (2010) 102-121 doi:10.1016/j.jalgebra.2010.02.035
LINKS
Murray Elder, Table of n, a(n) for n = 0..1500
J. Burillo, S. Cleary and B. Wiest, Computational explorations in Thompson's group F In Geometric Group Theory, Geneva and Barcelona Conferences, Birkhauser, 2007.
M. Elder, É. Fusy and A. Rechnitzer, Counting elements and geodesics in Thompson's group F, arXiv:0902.0202 [math.GR], 2009-2010.
V. S. Guba, On the Properties of the Cayley Graph of Richard Thompson's Group F, arXiv:math/0211396 [math.GR], 2002.
V. S. Guba, On the Properties of the Cayley Graph of Richard Thompson's Group F, Int. J. of Alg. Computation, 14(5-6):677-702, 2004.
EXAMPLE
For n=1 there are a(1)=4 elements: x_0, x_0^{-1}, x_1, x_1^{-1}.
CROSSREFS
KEYWORD
nonn
AUTHOR
Murray Elder, Feb 19 2009
STATUS
approved