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A156945 Growth sequence for Richard Thompson's group F with the standard generating set x_0,x_1. 2
1, 4, 12, 36, 108, 314, 906, 2576, 7280, 20352, 56664, 156570, 431238, 1180968, 3225940, 8773036, 23809148, 64388402, 173829458, 467950860, 1257901236, 3373450744, 9035758992 (list; graph; refs; listen; history; internal format)
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

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, E. Fusy and A. Rechnitzer, Counting elements and geodesics in Thompson's group $F$. Arxiv: 0902.0202

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.

LINKS

Murray Elder, Table of n, a(n) for n=0..1500

M. Elder, E. Fusy and A. Rechnitzer, Counting elements and geodesics in Thompson's group $F$

EXAMPLE

For n=1 there are a(1)=4 elements: x_0, x_0^{-1}, x_1, x_1^{-1}.

CROSSREFS

Sequence in context: A171849 A199937 A003212 * A006817 A163315 A003119

Adjacent sequences:  A156942 A156943 A156944 * A156946 A156947 A156948

KEYWORD

nonn

AUTHOR

Murray Elder (murrayelder(AT)gmail.com), Feb 19 2009

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Last modified February 16 13:56 EST 2012. Contains 205921 sequences.