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Specific Solution

Our interest in this paper is to solve the system equations 6 and 7 for the specific matrix given by Eq. 5.

We can verify by direct multiplication the relation


\begin{displaymath}
{1 \over \sqrt{5}}
\left[
\begin{array}{cc}
1 & 1 \\
- {...
...rray}{cc}
1 & 1 \\
1 & 0
\end{array}\right]
\; ,
\eqno(12)
\end{displaymath}

and so comparing to Eq. 9


\begin{displaymath}
\lambda_1 = {1-\sqrt{5} \over 2}
\eqno(13)
\end{displaymath}


\begin{displaymath}
\psi =
\lambda_2 = {1+\sqrt{5} \over 2}
\eqno(14)
\end{displaymath}

and


\begin{displaymath}
S =
\left[
\begin{array}{cc}
1 & 1 \\
- {{\sqrt{5}+1} \...
... 2} & {\sqrt{5}-1} \over 2
\end{array}\right]
\; .
\eqno(15)
\end{displaymath}

It is clear that $\lambda_1 \lambda_2 = -1$, so the $\lambda$'s are negative reciprocals. The number $\psi$ is called the golden ratio.

Multiplying out Eq. 11, making substitutions from Eqs. 13-15, performing some algebra, and taking the second element of the vector gives the desired representation for the $n^{th}$ Bob integer


\begin{displaymath}
x(n) = \left( {1 + \sqrt{5} \over 2} \right) ^{n+1}
+
\left( {1 - \sqrt{5} \over 2} \right) ^{n+1}
\; .
\eqno(16)
\end{displaymath}

This is a remarkable result!


next up previous contents
Next: Integer properties of Up: bobintegers Previous: Derivation of sequence term   Contents
Document created and compiled by George Schils. Copyright @2002 FEREGO. Copyright @2003-2009 George Schils. All rights reserved.