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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
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
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.)