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A214703
Primes that contain only the digits (2, 3, 5).
3
2, 3, 5, 23, 53, 223, 233, 353, 523, 2333, 3253, 3323, 3533, 5233, 5323, 5333, 23333, 25253, 25523, 32233, 32323, 32353, 32533, 33223, 33353, 33533, 35323, 35353, 35533, 52223, 52253, 52553, 53233, 53323, 53353, 55333, 222323, 222533, 222553, 223253, 225223
OFFSET
1,1
COMMENTS
The digits are prime numbers excluding 7.
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Vincenzo Librandi)
MATHEMATICA
Flatten[Table[Select[FromDigits/@Tuples[{2, 3, 5}, n], PrimeQ], {n, 7}]]
PROG
(Magma) [p: p in PrimesUpTo(300000) | Set(Intseq(p)) subset [2, 3, 5]];
(Python)
from sympy import isprime
from itertools import count, islice, product
def agen(): yield from (k for d in count(1) for k in (int("".join(p)) for p in product("235", repeat=d)) if isprime(k))
print(list(islice(agen(), 41))) # Michael S. Branicky, Dec 04 2022
CROSSREFS
Subsequence of A019546.
Cf. A087363 (primes with only prime digits excluding 2).
Sequence in context: A153477 A080016 A171432 * A327700 A182976 A042363
KEYWORD
nonn,base,easy
AUTHOR
Vincenzo Librandi, Jul 28 2012
STATUS
approved