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%I #15 Jul 22 2015 00:24:25
%S 3,5,53,353,3533,5333,33353,33533,35353,35533,53353,55333,333533,
%T 353333,533353,535333,3335533,3353333,3353533,3355553,3533533,3553553,
%U 3555353,5333353,5333533,5353553,5533553,33335333,33555553,35535553,35553533
%N Primes that contain digits 3 and 5 only.
%H Vincenzo Librandi, <a href="/A020462/b020462.txt">Table of n, a(n) for n = 1..1000</a>
%p sort(convert(`union`(seq(select(isprime,map(t -> 3*(10^d-1)/9 + 2*add(10^(s-1),s=t),combinat:-powerset(d))),d=0..10)),list)); # _Robert Israel_, Jul 21 2015
%t Flatten[Table[Select[FromDigits/@Tuples[{3,5},n],PrimeQ],{n,8}]] (* _Vincenzo Librandi_, Jul 27 2012 *)
%o (Python)
%o from gmpy2 import is_prime, mpz
%o from itertools import product
%o A020462_list = [int(''.join(x)) for n in range(1,10) for x in product('35',repeat=n) if is_prime(mpz(''.join(x)))] # _Chai Wah Wu_, Jul 21 2015
%K nonn,base
%O 1,1
%A _David W. Wilson_
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