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%I #21 Jun 23 2022 12:34:00
%S 23,37,53,73,223,227,233,257,277,337,353,373,523,557,577,727,733,757,
%T 773,22273,22277,22573,22727,22777,23227,23327,23333,23357,23537,
%U 23557,23753,23773,25237,25253,25357,25373,25523,25537,25577,25733,27253,27277
%N Primes with prime number of only prime digits (i.e., 2, 3, 5, 7).
%H Michael S. Branicky, <a href="/A124888/b124888.txt">Table of n, a(n) for n = 1..10000</a>
%H József Bölcsföldi, György Birkás, Miklós Ferenczi, <a href="http://www.ijmsi.org/Papers/Volume.5.Issue.2/B05020407.pdf">Bölcsföldi-Birkás-Ferenczi prime numbers (Full prime numbers)</a>, International Journal of Mathematics and Statistics Invention (IJMSI), Volume 5, Issue 2, February 2017, pp. 4-7.
%o (PARI) isok(p) = isprime(p) && (d=digits(p)) && isprime(#d) && vecmin(vector(#d, k, isprime(d[k]))); \\ _Michel Marcus_, Sep 21 2017
%o (Python)
%o from sympy import isprime, prime
%o from itertools import count, islice, product
%o def agen(): yield from filter(isprime, (int("".join(s)+e) for i in count(1) for s in product("2357", repeat=prime(i)-1) for e in "37"))
%o print(list(islice(agen(), 42))) # _Michael S. Branicky_, Jun 23 2022
%Y Cf. A019546, A120533.
%K nonn,base
%O 1,1
%A _Lekraj Beedassy_, Nov 12 2006
%E Terms 773, 23753 inserted by _Georg Fischer_, Jun 23 2022
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