Stage: 4 Challenge Level: 
You can do this by drawing trees for each case. Don't change the
order in the list of terms. You can only combine adjacent terms and
only two at a time.
epsilons. Patterned numbers. Mathematical reasoning & proof. Networks/Graph Theory. Algorithms. Mathematical induction. Combinatorics. Codes and cryptography. Dynamical systems. Fibonacci sequence.
Published October 2003.
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