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%I #15 Sep 08 2022 08:46:13
%S 5,7,557,577,757,5077,5507,5557,7057,7507,7577,7757,50077,50707,50777,
%T 55057,57077,57557,70507,75557,75577,75707,77557,500057,500777,505777,
%U 507077,507557,507757,550007,550577,550757,555077,555557,555707,557057,570077,575077
%N Primes that contain only the digits (0, 5, 7).
%H Alois P. Heinz, <a href="/A260827/b260827.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Prime[Range[2 10^5]], Complement[IntegerDigits[#], {0, 5, 7}]=={} &]
%o (Magma) [p: p in PrimesUpTo(2*10^6) | Set(Intseq(p)) subset [0,5,7]];
%o (Python)
%o from sympy import isprime
%o from sympy.utilities.iterables import multiset_permutations
%o def aupton(terms):
%o n, digits, alst = 0, 1, []
%o while len(alst) < terms:
%o mpstr = "".join(d*digits for d in "057")
%o for mp in multiset_permutations(mpstr, digits):
%o if mp[0] == "0": continue
%o t = int("".join(mp))
%o if isprime(t): alst.append(t)
%o if len(alst) == terms: break
%o else: digits += 1
%o return alst
%o print(aupton(38)) # _Michael S. Branicky_, May 07 2021
%Y A020467 is a subsequence.
%Y Cf. Primes that contain only the digits (k,5,7): this sequence (k=0), A260828 (k=1), A214705 (k=2), A087363 (k=3), A217039 (k=4), A260829 (k=6), A260830 (k=8), A260831 (k=9).
%Y Cf. A000040.
%K nonn,easy,base
%O 1,1
%A _Vincenzo Librandi_, Aug 01 2015
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