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\title{\Large\bf Automatic guessing and proof of the peoriod of Groudy function}
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\author{
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Xiangdong Wen
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\Section{Introduction} \label{sec-intro}
The groundy



\Section{Acknowledgment}
I wish to thank Dr. Zeilberger for his generous support and encouragement.


\begin{thebibliography}{9}
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\bibitem{Brinkhuis}
J.Brinkhuis,
``Non-repetitive sequences on three symbols'',
{\em Quart. J. Math}, Oxford(2), 145-149, 34(1983).

\bibitem{NZ}
John Noonan and Doron Zeilberger,
`` The Goulden-Jackson Cluster Method: Extensions, 
Applications, and Implementations'',
{\em J. Difference Eq. Appl.}, 355-377. 5(1999), 

\bibitem{Noonan}
John Noonan,
`` New Upper Bounds for The Connective Constants of Self-Avoiding Walks'',
{\em J. Stat. Phys.}, 871-888. 91(1998), 


\bibitem{CoGuy}
J.H. Conway and R.K. Guy,
``The book of numbers'',
{\em Copernicus, Springer, New York. } (1996).

\bibitem{MS}
N. Madras,and G. Slade, 
``The Self avoiding Walk'',
{\em } Birkhauser, Boston (1993).

\bibitem{GoJ1} I. Goulden  and D.M. Jackson,
{\em An inversion theorem for cluster decompositions of
sequences with distinguished subsequences},
J. London Math. Soc.(2){\bf 20} (1979), 567-576.
 
\bibitem{GoJ2} I. Goulden  and D.M. Jackson,
{\em "Combinatorial Enumeration"}, John  Wiley, 1983, New York.
 
\end{thebibliography}
  
{\bf Department of Mathematics, Temple University, Philadelphia,
PA 19122. wen@math.temple.edu}

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