A128388 - OEIS

%I #14 Sep 17 2019 16:03:15

%S 37,73,337,733,3257,3373,3527,3733,7253,7523,7577,7757,32233,32257,

%T 32353,32377,32537,33223,35227,35257,35323,35327,35537,72253,72337,

%U 72353,72577,73277,73327,73523,73553,75223,75253,75577,77237,77323

%N Emirps with only prime digits (i.e., 2, 3, 5, 7).

%C 7523 is the largest norep emirp with only prime digits. - _Harvey P. Dale_, Sep 17 2019

%H Harvey P. Dale, <a href="/A128388/b128388.txt">Table of n, a(n) for n = 1..2000</a>

%t Select[Prime@Range[10^4], # != r[ # ] && PrimeQ[r[ # ]] && Intersection[IntegerDigits[ # ], {0, 1, 4, 6, 8, 9}] == {} &] (* _Ray Chandler_, Mar 06 2007 *)

%t Table[Select[FromDigits/@Tuples[{2,3,5,7},n],!PalindromeQ[#]&& AllTrue[ {#, IntegerReverse[ #]},PrimeQ]&],{n,2,5}]//Flatten (* Requires Mathematica version 10 or later *)  (* _Harvey P. Dale_, Sep 17 2019 *)

%Y Cf. A006567, A128389, A128390.

%K base,less,nonn

%O 1,1

%A _Lekraj Beedassy_, Feb 28 2007

%E Corrected by _Ray Chandler_, Mar 06 2007