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A173580 Primes where each digit is 0, 1, 2, 4, or 8.

%I A173580 #30 Jun 12 2025 12:58:52
%S A173580 2,11,41,101,181,211,241,281,401,421,811,821,881,1021,1181,1201,1481,
%T A173580 1801,1811,2011,2081,2111,2141,2221,2281,2411,2441,2801,4001,4021,
%U A173580 4111,4201,4211,4241,4421,4441,4481,4801,8011,8081,8101,8111,8221,8821,10111
%N A173580 Primes where each digit is 0, 1, 2, 4, or 8.
%H A173580 Jason Bard, <a href="/A173580/b173580.txt">Table of n, a(n) for n = 1..10000</a>
%p A173580 with(numtheory): for n from 2 to 10000 do: l:=evalf(floor(ilog10(n))+1): n0:=n:indic:=0:for m from 1 to l do:q:=n0:u:=irem(q,10):v:=iquo(q,10): n0:=v : if u=3 or u= 5 or u= 6 or u=7 or u=9 then indic :=1 :else fi :od :if indic = 0 and type(n,prime) = true then print(n):else fi:od:
%t A173580 Join[{2}, Select[Map[FromDigits, Tuples[{0, 1, 2, 4, 8}, 3]]*10 + 1, PrimeQ]] (* _Paolo Xausa_, Jun 12 2025 *)
%o A173580 (Python)
%o A173580 from sympy import isprime
%o A173580 from itertools import count, islice, product
%o A173580 def agen(): # generator of terms
%o A173580     yield 2
%o A173580     yield from (t for digits in count(2) for f in "1248" for mid in product("01248", repeat=digits-2) if isprime(t:=int(f + "".join(mid) + "1")))
%o A173580 print(list(islice(agen(), 45))) # _Michael S. Branicky_, Jun 11 2025
%Y A173580 See A066593.
%Y A173580 Cf. A066591, A066592.
%K A173580 nonn,base
%O A173580 1,1
%A A173580 _Michel Lagneau_, Feb 22 2010