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 A020463 Primes that contain digits 3 and 7 only. 9
 3, 7, 37, 73, 337, 373, 733, 773, 3373, 3733, 7333, 33377, 33773, 37337, 77377, 77773, 333337, 333737, 373777, 377737, 733333, 733373, 737773, 773777, 777373, 777737, 3333373, 3333773, 3337333, 3337777, 3377377, 3733333, 3773377, 3773773, 3777377 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 MathOverflow, 3-7 primes in base 10 MATHEMATICA Flatten[Table[Select[FromDigits/@Tuples[{3, 7}, n], PrimeQ], {n, 7}]] (* Vincenzo Librandi, Jul 27 2012 *) CROSSREFS A143967, A020458. [From Reinhard Zumkeller, Sep 06 2008] Sequence in context: A260382 A260381 A260378 * A057625 A308392 A087208 Adjacent sequences:  A020460 A020461 A020462 * A020464 A020465 A020466 KEYWORD nonn,base AUTHOR STATUS approved

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Last modified December 13 20:27 EST 2019. Contains 329973 sequences. (Running on oeis4.)