New "graph" button

[N. J. A. Sloane]

Dear Seqfans,  Thanks to my colleague Debby Swayne (and
with help from Russ Cox), there is now a "graph" button
with each sequence. This shows two plots, a "pin" plot
of the terms that are given in the OEIS entry (the %S etc. lines),
and a scatter plot.  The scatter plot graphs the log_10 values
if that is appropriate, and uses the "b" file if one is available.

The plots are computed on the fly using "R", and take a couple
of seconds to appear.

Some examples to look at: A000010 (Euler phi),
A005132 (Recaman), A000045 (Fibonacci: note the second plot!),
A000041 (primes: note the second plot!).
It even works with sequences that no-one would expect to
be plottable, such as A008868 and A095646.
See also the test sequence A118131 (note second plot).

Let me know if there are any bugs.

We may add a special "plot" page later - at the foot of the OEIS pages -
that will have some of the additional features that people have suggested
(e.g. plotting one sequence against another, plotting
rational numbers, etc.)

Neil