# [seqfan] Re: Conway's subprime Fibonacci sequences

Wouter Meeussen wouter.meeussen at telenet.be
Tue Jul 24 19:10:01 CEST 2012

```let's not all do this simultaneously.
I'm ready & willing to oblige, anyone else busy on it right now?

Wouter.

-----Original Message-----
From: Neil Sloane
Sent: Tuesday, July 24, 2012 5:00 PM
To: Sequence Fanatics Discussion list
Cc: Julian Salazar
Subject: [seqfan] Re: Conway's subprime Fibonacci sequences

Tanya, Richard, Julian:

You should be aware of the paper by Back and Caragiu,
G. Back and M. Caragiu, The greatest prime factor and recurrent sequences,
Fib. Q., 48 (2010), 358-362.
which is closely related. Also sequences A175723, A177904, etc., which are
based on that paper.

Perhaps Julian could submit the sequence? - I see he is the primary author
of the ArXiv paper

Neil

On Tue, Jul 24, 2012 at 10:26 AM, Tanya Khovanova <
mathoflove-seqfan at yahoo.com> wrote:

> Dear SeqFans,
>
> I just coauthored a paper "Conway's subprime Fibonacci sequences" with
> Richard K. Guy and Julian Salazar. The paper is in the arxiv:
> http://arxiv.org/abs/1207.5099
>
> The main sequence (starting with 0,1) should be submitted. In July, I am
> working at RSI and do not have time to breath. Please, submit.
>
> The rule is: the next term is the sum of the two previous terms, and, if
> the sum is composite, it is divided by the least prime factor.
> Let me illustrate what is going on. First we start with two integers.
> Let's take 1 and 1 as in the Fibonacci sequence. Then the next term is
> 2, because it is prime and we do not divide by anything. The next two
> terms are 3 and 5. After that the sum of two terms is 8, which is now
> composite and it is divided by 2. So the sequence goes: 1, 1, 2, 3, 5,
> 4, 3, 7, 5, 6, 11 and so on.
>
>
> Tanya
>
> _______________________________________________
>
> 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