[seqfan] Re: Random question

[Edwin Clark]

On Mon, 5 Jan 2009, David Wilson wrote:

> This question occurred to me when I was looking at another seqfan post.
>
> For integer k > 0, is it always possible to find prime p such that the
> concatenation kp is prime?
>

The sequence kp is already in OEIS:

http://www.research.att.com/~njas/sequences/A089777

and characterized as "easy". I guess this is because it is so easy to find 
additional terms. In fact one can quickly find p among the first 148 
primes for all k up to 10^6. And for over 30% of k <= 10^6, p = 3 or 7 
will do. Proving there is always a suitable p is another matter!