# [seqfan] Re: The most and least interesting sequences not in OEIS

Felix Fröhlich felix.froe at gmail.com
Mon Sep 17 22:16:09 CEST 2018

```Keith, here are my thoughts:

Regarding the first suggestion: I thought of something similar a while ago:

Primes that were the largest known prime at some point in chronological
order.

Based on https://primes.utm.edu/notes/by_year.html, the sequence, beginning
with the year 1588, seems to start

131071, 524287, 2147483647, 3203431780337,
170141183460469231731687303715884105727

But so far, every time I thought about it I decided against submitting
this, mainly because I think it is ill defined. What exactly does it mean
for a prime to be the largest known prime? Known by whom? Etc, etc. Your
first suggestion seems to fall into the same category and, although I like
the idea, I think the sequence is not appropriate for the OEIS. (Again,
what exactly does it mean to be "known"? Known by whom?)

Regarding the second suggestion, I am a fan of sequences related to films
or television series myself. However, I think this particular sequence is
not appropriate. Again, I thought about something similar a while ago:

Number of episodes of the n-th Star Trek series. Based on
https://en.wikipedia.org/wiki/List_of_Star_Trek_episodes, the sequence, if
all series are included, would start

79, 22, 178, 176, 172, 98

And again, I am very hesitant to submit this, because it is probably of
limited interest and not very mathematical, and I think the same applies to
probably would not be accepted if submitted.

Best regards

Felix

Am Mo., 17. Sep. 2018 um 19:49 Uhr schrieb Andrew Weimholt <
andrew.weimholt at gmail.com>:

> I think BOTH of those sequences are the least interesting ones not in the
> OEIS,
> and should stay out of the OEIS.
>
>
> On Mon, Sep 17, 2018 at 6:22 AM Keith F. Lynch <kfl at keithlynch.net> wrote:
>
> > Here is the most interesting sequence I know of that is not in OEIS:
> >
> > 0  -250
> > 1  1400
> > 2  1706
> > 3  1949
> > 4  1958
> > 5  1961
> > 6  1973
> > 7  1983
> > 8  1987
> > 9  1989
> > 10 1997
> > 11 1999
> > 12 2002
> > 13 2011
> >
> > The nth term is when pi was first known to have been correctly
> > calculated to at least 10^n decimal places (or the equivalent
> > precision in some other notation).  It really shows the astonishing
> > progress in computer hardware and software.
> >
> > The 0th term is very uncertain.  Pi has been known to 10^0 place
> > precision for a very long time, but Archimedes is the first person
> > known to have *calculated* pi rather than measured it.  I'm not sure
> > in which decade he did so, but at least I have the century right.
> >
> > I wonder what the future of this sequence looks like.  When and what
> > will the last term be?  Or will it keep growing literally forever?
> >
> > It was rejected from OEIS.  I can understand why, since it isn't math,
> > even though it's about math.  But then why are A000053 or A007826 there?
> >
> > And here's the *least* interesting sequence I know of that is not
> > in OEIS:
> >
> > 17,11,19,24,30, 4,17,27,21,23,
> > 26, 1, 6, 3, 2, 7,11,10,23,28,
> > 27,26,25,30,29,28,27,25, 1,30
> >
> > The nth term is the day of the month that the nth season of The
> > Simpsons began (or will begin) on.  On noticing that the upcoming 30th
> > season is to begin on the 30th (of this month), I wondered if the nth
> > season had ever begun on the nth of the month before.  The a priori
> > odds are about 1 - (29/30.5)^29, which is about 0.77, so I figured it
> > most likely happened exactly once before.  And sure enough, it did.
> >
> > I have not submitted this sequence, and don't intend to.  I did check,
> > and sure enough it's not already there.  If someone else wants to
> > submit it, feel free to take the credit -- or the blame, as the case
> > may be.
> >
> > --
> > Seqfan Mailing list - http://list.seqfan.eu/
> >
>
> --
> Seqfan Mailing list - http://list.seqfan.eu/
>

```