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A210546 Emirps whose products of digits are prime.

%I A210546 #14 Aug 15 2017 20:40:20
%S A210546 13,17,31,71,113,311,1151,1511,111211,112111,1111711,1171111,11111117,
%T A210546 11113111,11131111,71111111,111111131,131111111,1111115111,1115111111,
%U A210546 11111111113,31111111111,111111111111111131,131111111111111111,1111111111111111111111111511
%N A210546 Emirps whose products of digits are prime.
%H A210546 Chai Wah Wu, <a href="/A210546/b210546.txt">Table of n, a(n) for n = 1..66</a>
%o A210546 (Python)
%o A210546 from __future__ import division
%o A210546 from sympy import isprime
%o A210546 A210546_list = []
%o A210546 for l in range(1,20):
%o A210546     q = (10**l-1)//9
%o A210546     for i in range(l):
%o A210546         for p in [2,3,5,7]:
%o A210546             r = q+(p-1)*10**i
%o A210546             s, t = str(r), str(r)[::-1]
%o A210546             if s != t and isprime(r) and isprime(int(t)):
%o A210546                 A210546_list.append(r) # _Chai Wah Wu_, Aug 15 2017
%Y A210546 Cf. A006567, A046703, A210547, A210548.
%K A210546 nonn,base
%O A210546 1,1
%A A210546 _Lekraj Beedassy_, Mar 22 2012
%E A210546 5 more terms from _Alois P. Heinz_, Mar 29 2012