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A124888
Primes with prime number of only prime digits (i.e., 2, 3, 5, 7).
3
23, 37, 53, 73, 223, 227, 233, 257, 277, 337, 353, 373, 523, 557, 577, 727, 733, 757, 773, 22273, 22277, 22573, 22727, 22777, 23227, 23327, 23333, 23357, 23537, 23557, 23753, 23773, 25237, 25253, 25357, 25373, 25523, 25537, 25577, 25733, 27253, 27277
OFFSET
1,1
LINKS
József Bölcsföldi, György Birkás, Miklós Ferenczi, Bölcsföldi-Birkás-Ferenczi prime numbers (Full prime numbers), International Journal of Mathematics and Statistics Invention (IJMSI), Volume 5, Issue 2, February 2017, pp. 4-7.
PROG
(PARI) isok(p) = isprime(p) && (d=digits(p)) && isprime(#d) && vecmin(vector(#d, k, isprime(d[k]))); \\ Michel Marcus, Sep 21 2017
(Python)
from sympy import isprime, prime
from itertools import count, islice, product
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"))
print(list(islice(agen(), 42))) # Michael S. Branicky, Jun 23 2022
CROSSREFS
Sequence in context: A092622 A129351 A179910 * A141521 A080906 A358421
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, Nov 12 2006
EXTENSIONS
Terms 773, 23753 inserted by Georg Fischer, Jun 23 2022
STATUS
approved