%I A003684
%S A003684 4,8,22,84,402,1218,3572,8218,11804
%N A003684 Number of n-digit reversible primes (or emirps) with distinct digits.
%e A003684 13, 17, 31, 37, 71, 73, 79 and 97 are reversible primes (emirps), so 
               a(2)=8.
%Y A003684 Cf. A006567, A007628, A046732, A048051, A048052, A048053, A048054, A048895.
%Y A003684 Sequence in context: A058855 A057583 A129788 this_sequence A075688 A026596 
               A083504
%Y A003684 Adjacent sequences: A003681 A003682 A003683 this_sequence A003685 A003686 
               A003687
%K A003684 nonn,fini,full,base,easy,nice
%O A003684 1,1
%A A003684 Harvey P. Dale (hpd(AT)apscompany.com) and Jud McCranie (j.mccranie(AT)comcast.net)
%E A003684 Typo in example corrected by David Ritterskamp (dritters(AT)usi.edu), 
               Mar 24 2008