[seqfan, OEIS-ideas] More sequence show-script ideas.
Antti Karttunen
Antti.Karttunen at iki.fi
Wed Jun 11 20:00:39 CEST 2003
Frank Ellermann wrote:
>
> P.S.: But I refuse to patch each and every subject only to keep
> _your_ inbound sorted by some obscure (for me) criteria
No, I wasn't forcing everybody to do the same... ;-)
But, yes, more formats are good for showtabl.c
However, I'm thinking also about something like
"a semi-intelligent sequence-plotter", i.e. from the
page generated by Sequence-link we could have
a Java-applet instantiated with the sequence terms
(and the keywords), and it would then plot the graph
of the sequence (interpreted as a "n -> f(n) function"),
automatically choicing an appropriate logarithmic
scale, depending on the growth rate of the sequence.
(Note that many EIS sequences exceed the 2^64 - 1 limit
of Java integers, so something like bignums would be necessary,
or a blunt error message, like "terms 7-9 of this sequence
could not be processed because too huge...")
Maybe one could also have a choice of toggling between different
logarithmic / straight scales in the Java applet display,
and also have a simple "star-plot", like:
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
which would be a nice feature for many "permutation of N" sequences.
(This example from from Wouter Meeussen's "Sun, 25 May 2003 18:13:51 +0200"
SeqFan-mail, "Re: fractal sequences",
for the sequence http://purl.net/net/eisa/A066194 )
I personally hate coding Java, but I could ask from sci.math
or similar newsgroup, whether anything like that has been coded
in Java or C and is available as open source,
or whether any volunteer would like to WRITE one from a scratch!
Other alternative would be to generate the plots and displays
like above at the OEIS side (e.g. using Boutell's on-the-fly
GIF-or-PNG drawing library), but I think that puts too much
burden there.
Yours,
Antti
More information about the SeqFan
mailing list