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% titlepage -----------------------
\title{\Large\bf Elliptic Curves and Convergence:\\Sato-Tate, GRH, and BSD}
\author{\large William Stein (joint work with Barry Mazur, with input from Andrew Granville,Chris Swierczewski and Tom Boothby)}
\date{2007-10-16}

% --------------------------------
\begin{document}

 \maketitle


\begin{frame}
\frametitle{Purpose}
\vfill
\Large

 Find a possible {\dred ``next question to ask''}, now that so
  much is understood {\dblue about the Sato-Tate conjecture} due to work of
  Taylor, Haris, et al.

\vfill

More generally study the general notion of {\dblue rate of convergence}
in the context of elliptic curves.

 \end{frame}


\begin{frame}
\frametitle{Hecke Eigenvalues}
\large
Let $E$ be a {\bf non-CM} elliptic curve over $\QQ$, and
$$
a_p = p+1-\#E(\mathbf{F}_p).
$$

\vfill
{\bf Theorem (Hasse):} $\displaystyle -1 < \frac{a_p}{2\sqrt{p}} < 1$.
\vfill

{\bf\dred Sato and Tate:} How are these numbers distributed?  A conjecture...
\begin{center}
\includegraphics[height=1.25in]{graphics/mikio_sato}
\hspace{1in}\includegraphics[height=1.25in]{graphics/tate_on_slide}
\end{center}

\end{frame}

\begin{frame}
\frametitle{Convergence to the semicircle distribution}
\large
The following slides each contain 8 plots. Each plot
displays the distribution of normalized $a_p$ for the lowest conductor
elliptic curves of different rank and all $a_p$ for $p < C$, for $C=10^3, 10^4, 10^5, 10^6$. 

\begin{center}
\begin{tabular}{ccc}
	Rank 0 & Rank 1 & Rank 2 \\
	Rank 3 & Rank 4 & Rank 5 \\
	Rank 6 & Rank 7 & Rank 8 \\
\end{tabular}
\end{center}

\end{frame}

\begin{frame}[fragile]
\frametitle{Sato-Tate Frequency Histograms: $C=10^3$}

\includegraphics[width=4in]{graphics/hist-1000.png}

\end{frame}

\begin{frame}
\frametitle{Sato-Tate Frequence Histograms: $C=10^4$}
\includegraphics[width=4in]{graphics/hist-10000.png}
\end{frame}


\begin{frame}
\frametitle{Sato-Tate Frequence Histograms: $C=10^5$}
\includegraphics[width=4in]{graphics/hist-100000.png}
\end{frame}

\begin{frame}
\frametitle{Sato-Tate Frequence Histograms: $C=10^6$}
\includegraphics[width=4in]{graphics/hist-1000000.png}
\end{frame}

\begin{frame}
\frametitle{Quantify the convergence?}
\LARGE
Barry Mazur: ``How can we precisely quantify the convergence of the {\dblue blue data} to the
{\dred red semicircle} theoretical distribution?''
\end{frame}


\begin{frame}
\frametitle{Some Functions (copy on blackboard)}
$E$ an elliptic curve; $a_p = p+1-\#E(\mathbf{F}_p)$
\vfill
\begin{itemize}
    \item 
    $\displaystyle X(T) =  \frac{\int_{-1}^T \sqrt{1-x^2}dx}{\int_{-1}^1 \sqrt{1-x^2}dx}= 
    \text{ area under arc of semicircle }$
\vfill
	\item 
	$\displaystyle 
	Y_{C}(T) = \frac{\#\left\{\text{primes }p < C : -1 < \frac{a_p}{2\sqrt{p}} < T\right\}}
	{\#\left\{\text{primes }p < C \right\}}$.
\vfill	
	\item $\displaystyle
	\Delta(C) = \sqrt{\int_{-1}^1 (X(T) - Y_{C}(T))^2 dT} =$ the $L_2$-norm of the difference of $X(T)$ and $Y_{C}(T)$, and $\Delta(C)_{\infty}$ the $L_{\infty}$-norm.

\end{itemize}
\end{frame}


\begin{frame}
\frametitle{The Sato-Tate Conjecture}
Let $\Delta(C)_{\infty}$ be the max of the difference
between the theoretical semicircle distribution and actual data using primes up to $C$.
 
\Huge
{\bf Sato-Tate Conjecture:}
$$
  \lim_{C\to\infty} \Delta(C)_{\infty} = 0
$$
\vfill
\Large {\bf\dblue Theorem (Taylor, M.~Harris, et al.):} If $E$ has multiplicative reduction
at some prime, then the Sato-Tate conjecture is true.    [Key part of proof
is to establish certain analytic properties of
symmetric power $L$-functions.]

\end{frame}

\begin{frame}[fragile]
\frametitle{Plotting $\Delta$ (up to $10^3$)}
{\dblue
\begin{verbatim}
sage: e37a = SatoTate(EllipticCurve('37a'), 10^6)
sage: show(e37a.plot_Delta(10^3, plot_points=400, 
 max_points=100), ymax=0.1, ymin=0, figsize=[10,3])
\end{verbatim}
}

\includegraphics[width=1.2\textwidth]{graphics/37a-plot_Delta-1000}


The {\dred red line is $\Delta(C)_{\infty}$} and the {\dblue blue line is $\Delta(C)$}.
By Sato-Tate, they both go to $0$ as $C\to\infty$.
\end{frame}

\begin{frame}[fragile]
\frametitle{Plotting $\Delta$ (up to $10^4$)}
{\dblue
\begin{verbatim}
sage: e37a = SatoTate(EllipticCurve('37a'), 10^6)
sage: show(e37a.plot_Delta(10^4, plot_points=200, 
 max_points=100), ymax=0.1, ymin=0, figsize=[10,3])
\end{verbatim}
}

\includegraphics[width=1.2\textwidth]{graphics/37a-plot_Delta-10000}


The {\dred red line is $\Delta(C)_{\infty}$} and the {\dblue blue line is $\Delta(C)$}.
By Sato-Tate, they both go to $0$ as $C\to\infty$.
\end{frame}

\begin{frame}[fragile]
\frametitle{Plotting $\Delta$ (up to $10^5$)}
{\dblue
\begin{verbatim}
sage: e37a = SatoTate(EllipticCurve('37a'), 10^6)
sage: show(e37a.plot_Delta(10^5, plot_points=200, 
 max_points=100), ymax=0.1, ymin=0, figsize=[10,3])
\end{verbatim}
}

\includegraphics[width=1.2\textwidth]{graphics/37a-plot_Delta-100000}


The {\dred red line is $\Delta(C)_{\infty}$} and the {\dblue blue line is $\Delta(C)$}.
By Sato-Tate, they both go to $0$ as $C\to\infty$.
\end{frame}

\begin{frame}[fragile]
\frametitle{Plotting $\Delta$ (up to $10^6$)}
{\dblue
\begin{verbatim}
sage: e37a = SatoTate(EllipticCurve('37a'), 10^6)
sage: show(e37a.plot_Delta(10^6, plot_points=200, 
 max_points=100), ymax=0.1, ymin=0, figsize=[10,3])
\end{verbatim}
}

\includegraphics[width=1.2\textwidth]{graphics/37a-plot_Delta-1000000}


The {\dred red line is $\Delta(C)_{\infty}$} and the {\dblue blue line is $\Delta(C)$}.
By Sato-Tate, they both go to $0$ as $C\to\infty$.
\end{frame}


\begin{frame}
\frametitle{``The next question to ask...''}
\LARGE

{\bf\dred QUESTION:} What 
about the speed of convergence?  I.e., {\em how} does
$\Delta(C)$ or $\Delta(C)_{\infty}$ converge to 0?
\vfill

\includegraphics[width=\textwidth]{graphics/37a-plot_Delta-1000000}

\end{frame}

\begin{frame}
\frametitle{The Akiyama-Tanigawa Conjecture}
\Large
{\dred \bf Conjecture (Akiyama-Tanigawa [Math Comp., 1999]):} For every 
$\epsilon>0$,  for $C\gg0$ we have
$$\Delta(C)_{\infty} \leq \frac{1}{C^{1/2-\epsilon}}.$$
\vfill
{\dblue Theorem (A-T):} This conjecture implies the {\dgreen Generalized Riemann Hypothesis} 
for $L(E,s)$.
\vfill
See Barry Mazur's forthcoming Notices paper for more discussion, references, and
pretty pictures. 
\end{frame}

\begin{frame}[fragile]
\frametitle{Converse}
{\dred Possibly GRH implies the above conjecture}:
\small
\begin{verbatim}
From: Shigeki Akiyama <akiyama@math.sc.niigata-u.ac.jp>
Date: Sun, 30 Sep 2007 08:17:02 +0900
Dear Professor Mazur

I feel very honored to have your comments on our old 
experimental paper. I was very pleased to read your 
expository paper itself, of course including 
subsections you wrote us. I did not consider the 
error term problem in this comprehensive manner,

My only comment is that a partial converse is true. 
If we assume Riemann hypothesis for all symmetric L, 
then the conjecture is valid for L_{0,1}. This is 
a claim from H. Nagoshi and basically comes from 
Erdos-Turan inequility as far as I remember... We 
did not explore nor publish this observation.
\end{verbatim}
\end{frame}

\begin{frame}
\frametitle{Log Plots}
\Large
Let's test out Akiyama-Tanigawa, instead of plotting $\Delta(C)$ which just
goes to $0$ quickly, {\dblue we instead plot $-\log_C(\Delta(C))$}.  

\begin{enumerate}
\item How does this function {\dred compare} to $\displaystyle \frac{1}{2}$?  I.e.,
does it eventually get within $\epsilon$ of $\frac{1}{2}$.

\item Can we find a simple function that conjecturally nicely {\dred approximates}
$-\log_C(\Delta(C))$?

\end{enumerate}




\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 0 curve 11a; $p < 10^6$; with 300 sample points}

\includegraphics[width=\textwidth]{graphics/11a-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 1 curve 37a; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/37a-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 2 curve 389a; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/389a-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 3 curve 5077a; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/5077a-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 4 curve [1,-1,0,-79,289]; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/rank4-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 5 curve [0, 0, 1, -79, 342]; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/rank5-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 6 curve [1, 1, 0, -2582, 48720]; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/rank6-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 7 curve [0, 0, 0, -10012, 346900]; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/rank7-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Rank 8 curve [0, 0, 1, -23737, 960366]; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/rank8-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Elkies rank $\geq 28$ curve; $p < 10^6$}

\includegraphics[width=\textwidth]{graphics/rank28-theta-1000000}

\vfill

\begin{itemize}
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item {\dred Red line is $1/2$.} 
\end{itemize}
{\bf OK, are those lines really going up to $1/2$???}

\end{frame}


\begin{frame}
\frametitle{Understanding the Data Better?}

\Large 
Can one {\dred predict} the asymptotic shape of the curve
$\Delta(C)$, say, in terms of either arithmetic invariants of the
curve or perhaps in terms of zeros of $L(E,s)$ on the critical strip?

\vfill
For some curves $\Delta(C)$ is quickly very close to $1/2$, e.g., the
curves of rank $0$ and $1$ above. 

\end{frame}

\begin{frame}[fragile]
\frametitle{Fitting the ``random'' Rank 0 curve $y^2 = x^3 +19x + 234$}
\includegraphics[width=\textwidth]{graphics/rank0-large_cond-fit}
\vfill
\begin{itemize}
\item
The black curve is 
$$
 \frac{1}{2} - \frac{1}{\log(X)}.
$$
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\item Conductor = $24093568 = 2^7 \cdot 41 \cdot 4591$
\end{itemize}
\end{frame}

\begin{frame}[fragile]
\frametitle{Low zeros?}
\small
{\dblue
\begin{verbatim}
sage: EllipticCurve('11a').Lseries_zeros(10)
[6.36261389, 8.60353962, 10.0355091,
 11.4512586, 13.5686391, 15.9140726,
 17.0336103, 17.9414336, 19.1857250,
 20.3792605]
\end{verbatim}
}

{\dred
\begin{verbatim}
sage: EllipticCurve([19,234]).Lseries_zeros(10)
[0.255961213, 0.739839807, 1.03144159,
 1.78804887, 2.11227980, 2.42762599,
 3.11102036, 3.26810134, 3.68155235,
 4.13888170]
\end{verbatim}
}
\end{frame}

\begin{frame}[fragile]
\frametitle{Fitting the Rank 3 Curve 5077a}
\includegraphics[width=\textwidth]{graphics/rank3-fit-1000000}
\vfill
\begin{itemize}
\item
The black curve is 
$$
 \frac{1}{2} - \frac{3/3}{\log(X)}.
$$
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Fitting the Rank 4 [1,-1,0,-79,289]; $p< 10^6$}
\includegraphics[width=\textwidth]{graphics/rank4-fit}
\vfill
\begin{itemize}
\item
The black curve is 
$$
 \frac{1}{2} - \frac{4/3}{\log(X)}.
$$
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Fitting Rank 8 [0, 0, 1, -23737, 960366]; $p< 10^6$}
\includegraphics[width=\textwidth]{graphics/rank8-fit}
\vfill
\begin{itemize}
\item
The black curve is 
$$
 \frac{1}{2} - \frac{19/9}{\log(X)}.
$$
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\end{itemize}

\end{frame}

\begin{frame}[fragile]
\frametitle{Fitting Rank 28 curve; $p< 10^6$}
\includegraphics[width=\textwidth]{graphics/rank28-fit}
\vfill
\begin{itemize}
\item
The black curve is 
$$
 \frac{1}{2} - \frac{28/9}{\log(X)}.
$$
\item {\dgreen Green line is $-\log_C(\Delta(C)_\infty)$.}
\item {\dblue Blue line is $-\log_C(\Delta(C))$}, with a grey tubular {\em numerical
integration error bound}. 
\end{itemize}

\end{frame}


\begin{frame}
\frametitle{Conjectural convergence of the measure of convergence}
{\bf\dblue Conjecture (Stein):}
For any $E$ there is a constant $\alpha$ such that 
$$
  -\log_C(\Delta(C)) \geq  \frac{1}{2} - \frac{\alpha}{\log(C)}
$$
{\bf for all} $C$.

\vfill

For comparison, recall the {\dred Akiyama-Tanigawa conjecture}
asserts that for all $\epsilon>0$, we have that
$$
   \Delta(C) \leq O\left(\frac{1}{C^{1/2-\epsilon}}\right)
$$

Equivalently,
$$
  -\log_C( \Delta(C)) \gg 1/2 - \epsilon
$$

\end{frame}

\begin{frame}
\frametitle{The Sato-Tate convergence parameter}

\vfill
For an elliptic curve $E$ let $\alpha(C)$ be the infimum of
all constants that minimizes the $L_2$ norm of this (i.e. the distance
between the black and blue curves above!):
$$
  -\log_C(\Delta(C)) - \left(  \frac{1}{2} - \frac{\alpha(C)}{\log(C)} \right).
$$
Thus $\alpha(C)$ is a function of $C$ (and the fixed curve $E$).
\vfill
\vfill
{\bf \dblue Definition:}
The {\em\dred Sate-Tate convergence parameter} of $E$ is
$$
  \alpha_E = \lim_{C\to\infty} \alpha(C).
$$
\vfill
(I don't know if this exists.  replace by limsup and liminf?)
\vfill
{\bf \dred Challenge:} Find a conjectural formula for $k_E$
in terms the critical zeros of $L(E,s)$? 

\end{frame}



\begin{frame}
\frametitle{Another future direction...}

We have
{\dblue $$
  X^{1/2 - 1/\log(X)} = \frac{X^{1/2}}{X^{1/\log(X)}}
 = e \cdot X^{1/2}.
$$}

We thus entertain the possibility (following the format of the people
who work with random matrices etc.) that the true distribution is well
approximated by something like
{\dblue
$$
  a \cdot (\log X)^b \cdot X^c
$$  }

\noindent for appropriate constants $a,b,c$. 

So for the rank $3$ example above we might choose
$$
  a= e, \qquad b= 0, \qquad c = 1/2,
$$ 
but there may be better choices?

\end{frame}

\begin{frame}
\frametitle{More future direction...}
\Large
\vfill
\begin{enumerate}
\item Restrict to intervals $[a,b]\subset (-1,1)$.  (This seems to have little to know impact.)
\vfill
\item Push computations much further (next slide).
\end{enumerate}
\vfill
\end{frame}


\begin{frame}
\frametitle{Pushing Computations Further}

\begin{enumerate}
\item {\dred Drew Sutherland} (of MIT) has some amazingly fast
  {\em parallel} C code for computing all $a_p$ for $p<C$ quickly (and
  much much more -- over 20,000 lines of new (pure) C code.
\item  On sage.math his code computes
all $a_p$ for $p < C=10^7$ in {\dblue less than $5$ seconds!}  
\item For comparison, $C=10^7$ takes Sage (via PARI) {\dblue 94 seconds} and
  Magma (via M Watkins' code) {\dred 81.25 seconds} (on sage.math, a 16-core opteron 246.).
\item Drew: {\dgreen ``My guess then is that on an idle system it would take
  about 5 minutes to do $p$ to $10^9$.''}
\end{enumerate}  



\end{frame}

\begin{frame}
\frametitle{GRH, BSD, and Convergence}
A related idea that Barry Mazur and I came up with recently:
\begin{enumerate}
\item Let $E$ be an elliptic curve over $\QQ$.
\item Construct a {\dred step function} like $\pi(X)$, but associated
to $E$, so each step is weighted by $a_p$.  
\item Construct an associated step function $\Psi(X)$ with steps
at the {\dred prime powers}.  The {\em distribution} $\Psi'(X)$ has
support at (most at) the prime powers.
\item Consider the {\dred distribution} $\Phi(t) = \Psi'(e^t)/e^{t/2}$.
\item It's {\dred Fourier transform} is 
$F(s) = \sum a_{p^n}{p^n} \log(p) \cos(n s \log(p)).$
\item GRH: The distribution $F(s)$ is discrete with 
support at the imaginary parts of the {\dred nontrivial
zeros of $L(E,s)$}. 
\item In particular, $F$ has a $\delta$ function at $0$ exactly
if $E$ has {\dred positive analytic rank}, i.e.,  $r_{E,\an} > 0$.
\item So study the rate of {\em divergence} of the sum
$$F(0) = \sum \frac{a_{p^n}}{p^n} \log(p).$$
\end{enumerate}
\end{frame}


\begin{frame}
\frametitle{A Numerical Experiment}
Let $$R_E(C) = \sum_{p^n\leq C} \frac{a_{p^n}}{p^n} \log(p).$$
\vfill
{\dblue Guess:} $R_E(C) \sim \alpha \log(C)^\beta$, where $\beta$
depends only on the rank of $E$ and $\alpha$ depends on
the arithmetic invariants of $E$.

\vfill
{\dblue Experiment:} Compute $\log(R_E(C)) / \log(\log(C))$.  Does
this depend only on rank of $E$?

\vfill
Next we give some {\dred data}.  In each case I give several curves
with a given rank, along with the value of the above
quantity for $C = 10^6$:
\vfill
\end{frame}

\begin{frame}[fragile]
\begin{verbatim}
curve     rank         log(R_E(C)) / log(log(C)) for C=10^6
37a1           1          0.622551283326
43a1           1          0.664628966956
53a1           1           0.64056834932
57a1           1          0.743607790253
58a1           1          0.639927175062
61a1           1          0.776549775927
65a1           1          0.717652219993

389a1          2           1.00758391471
433a1          2          0.988605592917
446d1          2            1.0273311084
563a1          2          0.987041109677
571b1          2          0.919099487872
643a1          2          0.889281143176
655a1          2          0.925749865705
664a1          2          0.957156816404
\end{verbatim}
\end{frame}


\begin{frame}[fragile]
\begin{verbatim}
curve     rank         log(R_E(C)) / log(log(C)) for C=10^6

5077a1         3           1.16071903587
11197a1        3           1.14902783005
11642a1        3           1.16976814614
12279a1        3           1.13108926023
13766a1        3           1.14886584781
16811a1        3           1.04598722161
18097b1        3           1.13427759105
18562c1        3           1.12453834551

234446a1       4           1.20905312451
19047851a1     5           1.29409998755
5187563742a1   6           1.34691224576
\end{verbatim}
\end{frame}

\begin{frame}
Because of the log-log's, etc., I'm probably getting 2
digits correct above usually, from the huge sum.
In pictures though, the lines are quickly fairly
horizontal (so the true limit is likely close to the above
numbers).

The striking thing about the above clumps of numbers
(for each rank), is they all lie in disjoint intervals.
\end{frame}

\end{document}







= Another perhaps related question =






