[seqfan] Re: Two neighboring digits multiply to a composite

[Eric Angelini]

Ahem, as Jim Nastos and Maximilian Hasler
wrote to me in private, the question asked
is phrased in globish -- and the sequence
not even correct ("4" comes twice).
My apologizes to the list -- posting
around two in the morning is never
a good idea...
Best,
É.
Envoyé d'un aPhone


Début du message transféré :

Expéditeur: Maximilian Hasler <maximilian.hasler at gmail.com<mailto:maximilian.hasler at gmail.com>>
Date: 18 avril 2012 05:05:42 HAEC
Destinataire: Eric Angelini <Eric.Angelini at kntv.be<mailto:Eric.Angelini at kntv.be>>
Objet: Rép : [seqfan] Two neighboring digits multiply to a composite

Maximilian



On Tue, Apr 17, 2012 at 8:15 PM, Eric Angelini <Eric.Angelini at kntv.be<mailto:Eric.Angelini at kntv.be>> wrote:

More on the same idea:

Smallest integer not yet in C such that
two neighboring digits multiply to a
composite:

hm, "multiply to a composite ?"

C = 1,4,2,3,4,5,6,7,8,9,14,16,18,19,22,

too many 4's ...


(and what about Z: smallest integer
not yet present in Z such that two
neighboring digits don't multiply to
a prime nor a composite. ;-)

c'est la oeis.org/A000012<http://oeis.org/A000012> ?

Bonne soirée (ou mieux : journée)

Maximilian