[seqfan] Re: First fini sequence in the table?

franktaw at netscape.net franktaw at netscape.net
Sun Dec 15 22:25:45 CET 2013


Did A000053 and 54 replace something else, then? Or how did they get so 
early?

Franklin T. Adams-Watters

-----Original Message-----
From: Neil Sloane <njasloane at gmail.com>

I agree with Charles's list .
However, as I remarked in the Preface to the 1973 book,
some sequences were given the benefit of the doubt, like
the sequence of Mersenne primes (which could still be a finite
sequence as far as anyone knows).
Neil


On Sun, Dec 15, 2013 at 1:31 PM, Charles Greathouse <
charles.greathouse at case.edu> wrote:

> It looks to me like the only finite sequences in the HIS were
>
> %N A000797 Numbers that are not the sum of 4 tetrahedral numbers.
> %N A000926 Euler's "numerus idoneus" (idoneal, or suitable, or 
convenient
> numbers).
> %N A001259 A sequence of sorted odd primes 3=p_1 < p_2 < ... < p_m 
such
> that p_i-2 divides the product p_1*p_2*...*p_(i-1) of the earlier 
primes
> and each prime factor of p_i-1 is a prime factor of twice the product.
> %N A002205 The RAND Corporation list of a million random digits.
> %N A003171 Discriminants of orders of imaginary quadratic fields with 
1
> class per genus (a finite sequence).
>
> so that seems a 5-way tie for priority in 1973.
>
> Charles Greathouse
> Analyst/Programmer
> Case Western Reserve University
>
>
> On Sun, Dec 15, 2013 at 12:55 PM, <franktaw at netscape.net> wrote:
>
> > By A-number, the first few fini sequences are A000053, A000054, 
A000797,
> > A000926, A001049, A001219, A001228, A001259, A001272, and A001293.
> >
> > On another issue, there are sequences such as A164081 that are 
finite in
> > the sense that from some point on they are zero. I think some such
> > sequences are marked "fini", while others (like A164081) just have 
lots
> of
> > zeros. We really ought to have a standard for this. (If we do decide
> these
> > should be marked finite, A000004 would  of course be an exception.)
> >
> > Franklin T. Adams-Watters
> >
> >
> > -----Original Message-----
> > From: Alonso Del Arte <alonso.delarte at gmail.com>
> > To: Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
> > Sent: Sun, Dec 15, 2013 11:39 am
> > Subject: [seqfan] First fini sequence in the table?
> >
> >
> > As most of us know, for a long time Neil excluded finite sequences,
> though
> > he made exceptions for sequences not known to be infinite (e.g., 
Mersenne
> > primes) and "for certain important number-theoretic sequences,such 
as
> > Euler's idoneal (or suitable) numbers."
> >
> > This raises the question: was A926 the first sequence in the OEIS 
known
> to
> > be finite? At what point were the keywords fini and full accepted?
> >
> > Al
> >
> > --
> > Alonso del Arte
> > Author at SmashWords.com<https://www.smashwords.com/profile/view/
> > AlonsoDelarte>
> > Musician at ReverbNation.com 
<http://www.reverbnation.com/alonsodelarte>
> >
> >
> > _______________________________________________
> >
> > Seqfan Mailing list - http://list.seqfan.eu/
> >
>
> _______________________________________________
>
> Seqfan Mailing list - http://list.seqfan.eu/
>



--
Dear Friends, I have now retired from AT&T. New coordinates:

Neil J. A. Sloane, President, OEIS Foundation
11 South Adelaide Avenue, Highland Park, NJ 08904, USA.
Also Visiting Scientist, Math. Dept., Rutgers University, Piscataway, 
NJ.
Phone: 732 828 6098; home page: http://NeilSloane.com
Email: njasloane at gmail.com

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