[seqfan] Re: Forcing of exact searches?
njasloane at gmail.com
Fri Aug 9 07:10:34 CEST 2019
The OEIS used to be on punched cards, and Russ has always made it
possible for me (and a couple of other people) to download a copy of the
in punched-card format. This is a flat ascii file. The file is called
cat25 (that name has not changed for 25 years, although the file has grown).
The current version (it is now a few weeks out of date) is:
$ wc cat25
5936314 53306288 408589671 cat25
That means it contains 5936314 (virtual) punched cards. It is what you see
if the click on "internal format" for a sequence.
It is nice to have this file, because I can grep in it for any string I
want to see.
I can do an exact search for any string.
The one annoying thing is that names with accents (like Erd****s) have
been distorted in the file, so it is hard to grep for them. (That is why I
always try to
give both the nonascii name (Erd****s) and the ascii name (Erdos) in
Of course, if you don't have a unix system, you are out of luck!
On Fri, Aug 9, 2019 at 12:15 AM Peter Munn <techsubs at pearceneptune.co.uk>
> I don't know how easy it would be to provide, but I offer this other
> example of when a "raw" search option would be useful. There are 70 to 80
> sequences that consist only of "1"s and "-1"s and I know no way to make
> the search distinguish the two values, making it more difficult to find
> such a sequence, and even more awkward to be sure such a sequence is
> Best Regards,
> On Thu, August 8, 2019 9:28 pm, Giovanni Resta wrote:
> > I did encounter the same problem many times and I tried a few variations
> > but it seems there is not an "exact" search.
> > For example, I was lookingÂ for powerful (A001694) numbers but since
> > "powerful" is translated to "power" I got thousands of results: I had to
> > enter a search like 4, 8, 9, 16, 25, 27, 32, 36, 49, 64, 72 to find the
> > actual sequence.
> > A simple search of a fixed string would be very useful.
> > Il 07/08/2019 09:57, Hugo Pfoertner ha scritto:
> >> SeqFans,
> >> is there a method to force "exact" searches for words?
> >> A search
> >> produces 922 hits, because the occurrence of "factor" also produces a -
> >> in
> >> my case unwanted - match.
> >> I can not see that the search hints https://oeis.org/hints.html deal
> >> with
> >> this problem.
> >> Hugo
> >> --
> >> Seqfan Mailing list - http://list.seqfan.eu/
> > --
> > Seqfan Mailing list - http://list.seqfan.eu/
> Seqfan Mailing list - http://list.seqfan.eu/
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