[seqfan] Re: Numbers such that the n-th and (n+1)st terms are the successors of prime numbers and primes themselves and n+1 > n

Charles Greathouse charles.greathouse at case.edu
Tue Nov 25 23:19:21 CET 2014


I corrected the program so it works -- but I haven't examined it to see
just what it is doing.

Charles Greathouse
Analyst/Programmer
Case Western Reserve University

On Tue, Nov 25, 2014 at 5:02 PM, Frank Adams-Watters <franktaw at netscape.net>
wrote:

> The PARI program in A075321 does not work.
>
> Franklin T. Adams-Watters
>
> -----Original Message-----
> From: Charles Greathouse <charles.greathouse at case.edu>
> To: Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
> Sent: Tue, Nov 25, 2014 2:13 pm
> Subject: [seqfan] Re: Numbers such that the n-th and (n+1)st terms are the
> successors of prime numbers and primes themselves and n+1 > n
>
>
> Indeed, it was just this sort of discrepancy that alerted me to the
> problem, since A147513 contains 51 = 3*17.
>
> Charles Greathouse
> Analyst/Programmer
> Case Western Reserve University
>
> On Tue, Nov 25, 2014 at 2:26 PM, David Applegate <david at research.att.com>
> wrote:
>
>  While poking around at this, I came across A075321,A075322, and
>>
> A075323.
>
>> These are based on "pair the odd primes so that the k-th pair is (p,
>>
> p+2k)"
>
>> The three sequences are the first in the pair, the second in the
>>
> pair, and
>
>> the pairs in order.
>>
>> As I read the description, every term should be prime.  However, when
>>
> I
>
>> look
>> at the sequence, I see 45, 55, 99, 115, 169, 201, 235, all of which
>>
> are
>
>> composite.  Are the sequences wrong, or does the definition need to be
>> cleaned
>> up?
>>
>> -Dave
>>
>> > From seqfan-bounces at list.seqfan.eu Tue Nov 25 13:51:54 2014
>> > Date: Tue, 25 Nov 2014 13:50:58 -0500
>> > From: Neil Sloane <njasloane at gmail.com>
>> > To: Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
>> > Subject: [seqfan] Re: Numbers such that the n-th and (n+1)st terms
>>
> are
>
>> the  successors of prime numbers and primes themselves and n+1 > n
>>
>> > That one (A147513) is certainly a mess.  If no one has a better
>>
> idea,
>
>> let's
>> > leave the terms intact, but give it keywords uned,obsc,unkn !
>>
>> > Best regards
>> > Neil
>>
>> > 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
>>
>> > On Tue, Nov 25, 2014 at 1:30 PM, Charles Greathouse <
>> > charles.greathouse at case.edu> wrote:
>>
>> > > Does anyone understand the definition of A147513? The terms start
>> > > 3, 5, 7, 11, 13, 19, 23, 31, 37, 47, 51
>> > > and no other information is given.
>> > >
>> > > Charles Greathouse
>> > > Analyst/Programmer
>> > > Case Western Reserve University
>> > >
>> > > _______________________________________________
>> > >
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>>
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>>
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