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 A335787 Emirps containing only the digits 1 and 3. 1
 13, 31, 113, 311, 113131, 131311, 1131131, 1133131, 1133333, 1311311, 1313311, 1331333, 1333313, 3111313, 3131113, 3133331, 3331331, 3333311, 11113111, 11131111, 11311133, 11313311, 11331311, 11333131, 13131133, 13133311, 31111313, 31311113, 33111311, 33113131 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Daniel Starodubtsev, Table of n, a(n) for n = 1..10000 MATHEMATICA 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 *) CROSSREFS Intersection of A006567 and A032917. Subsequence of A020451. Sequence in context: A179034 A179035 A007628 * A141837 A299888 A023304 Adjacent sequences: A335784 A335785 A335786 * A335788 A335789 A335790 KEYWORD nonn,base AUTHOR Daniel Starodubtsev, Jun 23 2020 STATUS approved

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Last modified April 12 22:48 EDT 2024. Contains 371639 sequences. (Running on oeis4.)