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%I #14 Jul 20 2020 13:07:39
%S 13,31,113,311,113131,131311,1131131,1133131,1133333,1311311,1313311,
%T 1331333,1333313,3111313,3131113,3133331,3331331,3333311,11113111,
%U 11131111,11311133,11313311,11331311,11333131,13131133,13133311,31111313,31311113,33111311,33113131
%N Emirps containing only the digits 1 and 3.
%H Daniel Starodubtsev, <a href="/A335787/b335787.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Flatten[Table[FromDigits[#, 10] & /@ Tuples[{1, 3}, n], {n, 8}]], # != (r = IntegerReverse[#]) && PrimeQ[#] && PrimeQ[r] &] (* _Amiram Eldar_, Jun 23 2020 after _Vincenzo Librandi_ at A032917 *)
%Y Intersection of A006567 and A032917.
%Y Subsequence of A020451.
%K nonn,base
%O 1,1
%A _Daniel Starodubtsev_, Jun 23 2020
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