[seqfan] Re: How about

[Maximilian Hasler]

On Fri, Mar 27, 2009 at 4:41 PM, David Wilson <dwilson at gambitcomm.com> wrote:
> Primes that are either single digit primes or a concatenation of (two)
> earlier sequence elements.

isDW(p,i=1)={while(p>i*=10,setminus(Set(divrem(p,i)),a)|return(eval(Set(Vec(Str(p)))[1])));p<9}
a=[]; forprime( p=2, 99999, isDW(p) & !print1(p",") & a=setunion(a,Set(p)))

2,3,5,7,23,37,53,73,223,233,337,353,373,523,733,773,2237,2333,3373,3533,
3733,5233,5237,5323,7333,7523,23333,23773,25237,32237,33533,33773,
35323,35353,37223,37337,52237,53233,53353,53773,73523,75323,77323,...

Maximilian