Primefree sequences in the OEIS. A bad idea.

[Thomas Baruchel]

On Dim, oct 30, 2005 at 07:59:36 +0200, Alexandre Wajnberg wrote:
> It raises the necessity to have the possibility to "filter" the database
> (for any personal scientific use). How to exclude <non-research sequences>
> from a search?

Maybe a new flag meaning that numbers in the sequence have a significance
from a computational point of view, which would exclude : base-related
sequences (since 123456 being in the database because of some property
in base 7 or 10 has no "computational" significance - a flag for "base
related" would also be nice, but maybe there is already one ?), sequences
referring to other sequences, and probably also some puzzle sequences.
In fact it would be nice to have the ability to filter sequences which
may be used for "identifying an unknown sequence" (for me, most often
I manage to do this by comparing big prime factors in my numerators
or denominators with big prime factors appearing in my computations),
since other sequence, despite their own value, will probably never help
someone identifying numbers. Maybe I am wrong, but for me the OEIS is
for sequences what Plouffe's inverter is for numbers.

Note that I don't blame anything, but would be even more happy if I had
to possibility to build my own short version of the database with
sequences that could really help me (for the moment, 2500 ones thanks
to some "grep"), but I think that more than 10,000 or 25,000 should be the
real right number.

Regards,

-- 
Thomas Baruchel
  Home Page: http://baruchel.free.fr/~thomas/