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%I #18 Mar 04 2018 03:20:48
%S 2,3,5,7,23,37,53,73,223,233,337,353,373,523,733,773,2237,2333,3373,
%T 3533,3733,5233,5237,5323,7333,7523,23333,23773,25237,32237,33533,
%U 33773,35323,35353,37223,37337,52237,53233,53353,53773,73523,75323,77323
%N Primes that are either single-digit primes or a concatenation of two earlier terms.
%H Jean-Marc Falcoz, <a href="/A104179/b104179.txt">Table of n, a(n) for n = 1..1003</a>
%F Up to 10^12 there are only 1003 terms and the n-th term seems to be roughly n^(10/e). - _Jean-Marc Falcoz_, Mar 28 2009
%o (PARI) isDW(p,i=1)={while(p>i*=10,setminus(Set(divrem(p,i)),a)|return(eval(Set(Vec(Str(p)))[1])));p<9}
%o a=[]; forprime( p=2, 99999, isDW(p) & !print1(p",") & a=setunion(a,Set(p))) \\ _M. F. Hasler_, Mar 28 2009
%K nonn,base
%O 1,1
%A _David W. Wilson_, Mar 27 2009
%E More terms from _M. F. Hasler_, Mar 28 2009
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